Leases (Details) - USD ($)	Dec. 31, 2019	Oct. 01, 2019	May 06, 2019
Operating Leased Assets [Line Items]
Operating lease right-of-use assets		$ 380,000,000
Operating lease, liability	$ 376,000,000	384,000,000
Right of use asset, impairment		$ 4,000,000
Weighted average remaining lease term	6 years
Weighted average discount rate	5.50%
7.00% Notes due in 2026 | Unsecured debt
Operating Leased Assets [Line Items]
Face amount of debt			$ 800,000,000