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Retirement Benefits (Tables)
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9 Months Ended |
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Sep. 30, 2013
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| Defined Benefit Plan Disclosure [Line Items] |
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| Schedule Of Net Benefit Costs |
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In Millions
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Pension
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OPEB
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Three Months Ended
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Nine Months Ended
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Three Months Ended
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Nine Months Ended
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2013
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2012
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2013
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2012
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2013
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2012
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2013
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2012
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CMS Energy, including Consumers
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Net periodic cost (credit)
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Service cost
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$
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13
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$
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12
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$
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40
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$
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36
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$
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5
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$
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8
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$
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23
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$
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24
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Interest expense
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23
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24
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70
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74
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14
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21
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52
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62
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Expected return on plan assets
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(32)
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(31)
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(96)
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(94)
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(20)
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(17)
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(58)
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(50)
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Amortization of:
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Net loss
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24
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19
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72
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57
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3
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12
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24
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35
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Prior service cost (credit)
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1
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1
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3
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4
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(10)
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(5)
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(20)
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(15)
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Net periodic cost (credit)
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$
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29
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$
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25
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$
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89
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$
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77
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$
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(8)
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$
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19
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$
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21
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$
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56
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Consumers
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Net periodic cost (credit)
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Service cost
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$
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13
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$
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12
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$
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39
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$
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35
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$
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5
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$
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7
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$
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23
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$
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23
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Interest expense
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23
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24
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69
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72
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14
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20
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50
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60
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Expected return on plan assets
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(31)
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(30)
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(94)
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(91)
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(19)
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(15)
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(54)
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(46)
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Amortization of:
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Net loss
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23
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18
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70
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55
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3
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12
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24
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35
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Prior service cost (credit)
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1
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1
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3
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4
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(10)
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(5)
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(20)
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(15)
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Net periodic cost (credit)
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$
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29
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$
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25
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$
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87
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$
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75
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$
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(7)
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$
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19
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$
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23
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$
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57
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Consumers Energy Company [Member]
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|
| Defined Benefit Plan Disclosure [Line Items] |
|
| Schedule Of Net Benefit Costs |
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In Millions
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Pension
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OPEB
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Three Months Ended
|
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Nine Months Ended
|
|
Three Months Ended
|
|
Nine Months Ended
|
|
|
|
2013
|
2012
|
2013
|
2012
|
|
2013
|
2012
|
2013
|
2012
|
|
|
CMS Energy, including Consumers
|
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|
|
|
|
|
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Net periodic cost (credit)
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Service cost
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$
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13
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$
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12
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$
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40
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$
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36
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$
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5
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$
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8
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$
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23
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$
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24
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Interest expense
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23
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24
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70
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74
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14
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21
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52
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62
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Expected return on plan assets
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|
(32)
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|
(31)
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|
(96)
|
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|
(94)
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(20)
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(17)
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(58)
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(50)
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Amortization of:
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Net loss
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24
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19
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72
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57
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3
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12
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24
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35
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Prior service cost (credit)
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1
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1
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3
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4
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(10)
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(5)
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(20)
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(15)
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Net periodic cost (credit)
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$
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29
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$
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25
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$
|
89
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$
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77
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$
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(8)
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$
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19
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$
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21
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$
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56
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Consumers
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Net periodic cost (credit)
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Service cost
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$
|
13
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$
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12
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$
|
39
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$
|
35
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$
|
5
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$
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7
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$
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23
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$
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23
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Interest expense
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23
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24
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69
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72
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14
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20
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50
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60
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Expected return on plan assets
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|
(31)
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(30)
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(94)
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(91)
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(19)
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(15)
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(54)
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(46)
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Amortization of:
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Net loss
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23
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18
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70
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55
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3
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12
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24
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35
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Prior service cost (credit)
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1
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1
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3
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4
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(10)
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(5)
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(20)
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(15)
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Net periodic cost (credit)
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$
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29
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$
|
25
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$
|
87
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$
|
75
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$
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(7)
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$
|
19
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$
|
23
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$
|
57
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