Consolidating Condensed Financial Information - Additional Information (Details)	Sep. 30, 2019	Oct. 01, 2018	Sep. 30, 2018	Sep. 20, 2018	Sep. 13, 2017	Mar. 29, 2017	Jul. 23, 2015
7% Senior Notes Due 2023
Condensed Financial Statements Captions [Line Items]
Interest rate (as a percent)	7.00%						7.00%
6% Senior Notes due 2025
Condensed Financial Statements Captions [Line Items]
Interest rate (as a percent)	6.00%				6.00%	6.00%
6% Senior Notes due 2026
Condensed Financial Statements Captions [Line Items]
Interest rate (as a percent)	6.00%	6.00%	6.00%	6.00%