Derivatives - Narrative (Details) - USD ($)	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Derivative Instruments, Gain (Loss) [Line Items]
Net Asset (Liability)	$ 31,000,000		$ 6,000,000
Interest rate swap gain (loss) to be reclassified during next twelve months	0
Interest Rate
Derivative Instruments, Gain (Loss) [Line Items]
Deferred loss related to interest rate swaps	10,000,000
Interest Rate | Not Designated as Hedges
Derivative Instruments, Gain (Loss) [Line Items]
Net Asset (Liability)	(2,000,000)	$ (7,000,000)	0
Cash Flow Hedges
Derivative Instruments, Gain (Loss) [Line Items]
Net Asset (Liability)	(10,000,000)		2,000,000
Cash Flow Hedges | Interest Rate
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount			$ 320,000,000
Notes Due 2025 | Cash Flow Hedges | Interest Rate
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, notional amount	$ 350,000,000