REGULATORY ASSETS AND LIABILITIES (Details) - USD ($)
$ in Thousands |
3 Months Ended |
6 Months Ended |
12 Months Ended |
|
Jun. 30, 2020 |
Jun. 30, 2019 |
Jun. 30, 2020 |
Jun. 30, 2019 |
Dec. 31, 2017 |
Dec. 31, 2019 |
| SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items] |
|
|
|
|
|
|
| Kansas Gas Service tax reform regulatory liability |
$ 81,500
|
|
$ 81,500
|
|
|
|
| Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent |
|
|
21.00%
|
|
35.00%
|
|
| Regulatory Assets, Current |
47,961
|
|
$ 47,961
|
|
|
$ 47,440
|
| Regulatory Assets, Noncurrent |
373,241
|
|
373,241
|
|
|
391,036
|
| Regulatory Liability, Current |
(26,163)
|
|
(26,163)
|
|
|
(45,201)
|
| Regulatory Liability, Noncurrent |
(558,115)
|
|
(558,115)
|
|
|
(503,518)
|
| Net regulatory assets (liabilities), current |
21,798
|
|
21,798
|
|
|
2,239
|
| Net regulatory assets (liabilities), noncurrent |
(184,874)
|
|
(184,874)
|
|
|
(112,482)
|
| Net Regulatory Assets |
(163,076)
|
|
(163,076)
|
|
|
(110,243)
|
| Reduction in income tax expense for the amortization of the regulatory liability associated with excess ADIT that was returned to customers |
2,500
|
$ 2,100
|
9,400
|
$ 8,900
|
|
|
| Income tax rate changes [Member] [Domain] |
|
|
|
|
|
|
| SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items] |
|
|
|
|
|
|
| Regulatory Liability, Current |
(2,265)
|
|
(2,265)
|
|
|
(10,297)
|
| Regulatory Liability, Noncurrent |
(558,115)
|
|
(558,115)
|
|
|
(503,518)
|
| Regulatory Liabilities |
(560,380)
|
|
(560,380)
|
|
|
(513,815)
|
| Over-recovered purchased-gas costs [Member] |
|
|
|
|
|
|
| SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items] |
|
|
|
|
|
|
| Regulatory Liability, Current |
(23,898)
|
|
(23,898)
|
|
|
(27,623)
|
| Regulatory Liability, Noncurrent |
0
|
|
0
|
|
|
0
|
| Regulatory Liabilities |
(23,898)
|
|
(23,898)
|
|
|
(27,623)
|
| Total regulated liabilities [Member] |
|
|
|
|
|
|
| SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items] |
|
|
|
|
|
|
| Regulatory Liability, Current |
(26,163)
|
|
(26,163)
|
|
|
(45,201)
|
| Regulatory Liability, Noncurrent |
(558,115)
|
|
(558,115)
|
|
|
(503,518)
|
| Regulatory Liabilities |
(584,278)
|
|
(584,278)
|
|
|
(548,719)
|
| Under-recovered purchased-gas costs [Member] |
|
|
|
|
|
|
| SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items] |
|
|
|
|
|
|
| Regulatory Assets, Current |
7,247
|
|
7,247
|
|
|
17,172
|
| Regulatory Assets, Noncurrent |
0
|
|
0
|
|
|
0
|
| Regulatory Assets |
7,247
|
|
7,247
|
|
|
17,172
|
| Pension and postretirement benefit costs [Member] |
|
|
|
|
|
|
| SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items] |
|
|
|
|
|
|
| Regulatory Assets, Current |
21,156
|
|
21,156
|
|
|
21,213
|
| Regulatory Assets, Noncurrent |
353,616
|
|
353,616
|
|
|
373,266
|
| Regulatory Assets |
374,772
|
|
374,772
|
|
|
394,479
|
| Weather normalization [Member] |
|
|
|
|
|
|
| SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items] |
|
|
|
|
|
|
| Regulatory Assets, Current |
4,674
|
|
4,674
|
|
|
|
| Regulatory Assets, Noncurrent |
0
|
|
0
|
|
|
|
| Regulatory Assets |
4,674
|
|
4,674
|
|
|
|
| Regulatory Liability, Current |
|
|
|
|
|
(7,281)
|
| Regulatory Liability, Noncurrent |
|
|
|
|
|
0
|
| Regulatory Liabilities |
|
|
|
|
|
(7,281)
|
| Reacquired debt costs [Member] |
|
|
|
|
|
|
| SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items] |
|
|
|
|
|
|
| Regulatory Assets, Current |
812
|
|
812
|
|
|
812
|
| Regulatory Assets, Noncurrent |
5,271
|
|
5,271
|
|
|
5,677
|
| Regulatory Assets |
6,083
|
|
6,083
|
|
|
6,489
|
| MGP Costs [Member] [Member] |
|
|
|
|
|
|
| SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items] |
|
|
|
|
|
|
| Regulatory Assets, Current |
98
|
|
98
|
|
|
98
|
| Regulatory Assets, Noncurrent |
11,660
|
|
11,660
|
|
|
9,709
|
| Regulatory Assets |
11,758
|
|
11,758
|
|
|
9,807
|
| Ad valorem tax [Member] |
|
|
|
|
|
|
| SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items] |
|
|
|
|
|
|
| Regulatory Assets, Current |
4,095
|
|
4,095
|
|
|
2,921
|
| Regulatory Assets, Noncurrent |
0
|
|
0
|
|
|
0
|
| Regulatory Assets |
4,095
|
|
4,095
|
|
|
2,921
|
| Other regulatory assets [Member] |
|
|
|
|
|
|
| SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items] |
|
|
|
|
|
|
| Regulatory Assets, Current |
9,879
|
|
9,879
|
|
|
5,224
|
| Regulatory Assets, Noncurrent |
2,694
|
|
2,694
|
|
|
2,384
|
| Regulatory Assets |
12,573
|
|
12,573
|
|
|
7,608
|
| Total regulatory assets, net of amortization [Member] |
|
|
|
|
|
|
| SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items] |
|
|
|
|
|
|
| Regulatory Assets, Current |
47,961
|
|
47,961
|
|
|
47,440
|
| Regulatory Assets, Noncurrent |
373,241
|
|
373,241
|
|
|
391,036
|
| Regulatory Assets |
$ 421,202
|
|
$ 421,202
|
|
|
$ 438,476
|