Long Term Debt Activity - Additional Information (Detail) - USD ($) $ in Thousands				9 Months Ended
	Jun. 13, 2016	May 16, 2016	Mar. 21, 2016	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Debt Instrument [Line Items]
Loss on debt amendments and refinancing				$ 13,284	$ 925
Principal amount redeemed				200,000
Write off of unamortization of debt issuance cost				2,369
Carrying value of long-term debt				1,824,355		$ 1,814,572
Fair value of long-term debt				1,839,380		$ 1,806,276
7.375% senior subordinated notes due 2021
Debt Instrument [Line Items]
Loss on debt amendments and refinancing				1,222
Interest rate			7.375%
Principal amount redeemed			$ 200,000
Percentage of debt repayment premium			104.00%
Write off of unamortization of debt issuance cost			$ 2,369
Early retirement of debt			9,444
4.875 % Senior Notes Due June 1, 2023
Debt Instrument [Line Items]
Debt issuance costs				3,702
Aggregate principal amount issued			$ 225,000	$ 755,000
Interest rate			4.875%	4.875%
Price to repurchase the senior subordinated notes as a percentage of the aggregate principal amount outstanding plus accrued and unpaid interest in case of change of control			99.00%
Debt instrument, maturity date				Jun. 01, 2023
Debt issue costs, discount				$ 2,250
Senior Secured Credit Facility Agreement
Debt Instrument [Line Items]
Pre-payment of term loan		$ 13,451
Quarterly principal payments due		$ 1,427
First quarterly payment date		Jun. 30, 2017
Last quarterly payment date		Mar. 31, 2022
Remaining principal		$ 635,250
Remaining principal due date		May 08, 2022
Debt instrument, reduction in interest rate	(0.25%)
Debt issuance costs				802
Loss on debt amendments and refinancing				$ 249