CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical)	Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2018
5 3/4% Senior Notes due April 15, 2019
Stated interest rate	5.75%	5.75%
5.875% Senior Notes due January 31, 2025
Stated interest rate	5.875%	5.875%
7% Senior Notes due August 15, 2022
Stated interest rate	7.00%	7.00%
6% Senior Notes due September 1, 2023
Stated interest rate	6.00%	6.00%
6.625% Senior Notes Due 2027
Stated interest rate	6.625%	6.625%	6.625%