SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS
 12 Months Ended
Dec. 31, 2019
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]  
SCHEDULE II-VALUATION AND QUALIFYING ACCOUNTS
SCHEDULE II—VALUATION AND QUALIFYING ACCOUNTS
For the Years Ended December 31, 2019, 2018, and 2017
(in millions)
 
 
 
 
 
 
Additions
 
 
 
 
 
 
Balance  at
Beginning
of Period
 
Acquired/(Disposed)
Balances
 
Charged
(Credited)  to
Costs and
Expenses
 
Charged  to
Other
Accounts (1)
 
Deductions
or
Write-offs
 
Balance at
End  of
Period
Allowance for loss on receivables:
 
 
 
 
 
 
 
 
 
 
 
 
2019
 
$
79

 
$
—

 
$
(1
)
 
$
—

 
$
(9
)
 
$
69

2018
 
96

 
—

 
36

 
(29
)
 
(24
)
 
79

2017
 
118

 
—

 
20

 
(10
)
 
(32
)
 
96

Deferred tax asset valuation allowance:
 
 
 
 
 
 
 
 
 
 
 
 
2019
 
(54
)
 
—

 
9

 
—

 
—

 
(45
)
2018
 
(49
)
 
—

 
(5
)
 
—

 
—

 
(54
)
2017
 
(49
)
 
—

 
—

 
—

 
—

 
(49
)
(1)
Represents changes in retroactive membership adjustments to premiums revenue and contractual allowances adjustments to services revenue as more fully described in Note 2 to the consolidated financial statements included in this annual report on Form 10-K.