Components of Interest Expense (Detail) - USD ($) $ in Thousands	4 Months Ended	8 Months Ended	12 Months Ended
	Dec. 31, 2016	Sep. 12, 2016	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument, Redemption [Line Items]
Contractual Interest Expense on Prepetition Liabilities Not Recognized in Statement of Operations		$ 66,100
Debtor Reorganization Items, Write-off of Debt Issuance Costs and Debt Discounts		20,500
Interest on borrowings and related fees 1	$ 678	36,012	$ 92,490	$ 91,866
Amortization of debt issuance costs 2	226	22,189	4,749	4,197
Capitalized interest	(25)	(183)	(6,288)	(7,232)
Interest expense	$ 879	58,018	$ 90,951	$ 88,831
Senior Notes Due 2019 [Member]
Debt Instrument, Redemption [Line Items]
Contractual Interest Expense on Prepetition Liabilities Not Recognized in Statement of Operations		15,300
Senior Notes Due 2020 [Member]
Debt Instrument, Redemption [Line Items]
Contractual Interest Expense on Prepetition Liabilities Not Recognized in Statement of Operations		$ 46,300