Derivatives - Interest-Rate Derivatives (Details) $ in Millions	3 Months Ended
Mar. 31, 2020 USD ($)
Interest Rate Swap, 6.835%
Derivative [Line Items]
Notional Principal Amount	$ 400
Weighted-Average Interest Rate	6.348%
Interest Rate Swap, 6.891%
Derivative [Line Items]
Notional Principal Amount	$ 350
Weighted-Average Interest Rate	6.662%
Interest Rate Swap, 6.570%
Derivative [Line Items]
Notional Principal Amount	$ 275
Weighted-Average Interest Rate	6.709%
Interest Rate Swap, 6.445%
Derivative [Line Items]
Notional Principal Amount	$ 450
Weighted-Average Interest Rate	6.445%
Interest Rate Swaps
Derivative [Line Items]
Net cash payments related to settlements and amendments	$ 50
Collateralization of interest rate swap	$ 99

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

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- Definition

Average fixed interest rate related to the group of interest rate derivatives.

+ References

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- Definition

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
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- Definition

The cash outflow for derivative instruments during the period, which are classified as financing activities, excluding those designated as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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