Subsequent Events - Narrative (Details) - Unsecured Senior Notes - USD ($)	Feb. 29, 2020	Jan. 16, 2020	Dec. 31, 2019
Subsequent Event [Line Items]
Face amount			$ 2,398,000,000
$600 Senior Notes, 6% | Subsequent Event
Subsequent Event [Line Items]
Face amount		$ 600,000,000
Interest rate		6.00%
$300 face value, 6.500% interest rate payable semi-annually, due June 2022
Subsequent Event [Line Items]
Face amount			$ 300,000,000
Interest rate			6.50%
$300 face value, 6.500% interest rate payable semi-annually, due June 2022 | Subsequent Event
Subsequent Event [Line Items]
Interest rate	6.50%