Consolidated Statements of Cash Flows (Parenthetical)	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	May 19, 2017	Oct. 03, 2016
6.125% Senior Notes due 2024
Debt Instrument [Line Items]
Debt instrument, interest rate, stated (as a percent)	6.125%		6.125%	6.125%	6.125%
6.375% Senior Notes due 2026
Debt Instrument [Line Items]
Debt instrument, interest rate, stated (as a percent)	6.375%	6.375%