Debt - Additional Information (Detail) - USD ($)		3 Months Ended		9 Months Ended
	Jul. 06, 2015	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Jul. 13, 2015	Mar. 31, 2014
Debt Instrument [Line Items]
Debt instrument interest rate		8.875%		8.875%
Loss on extinguishment of debt		$ (59,392,000)		$ (59,392,000)
Debt instrument, covenant description				The Indenture contains covenants that, among other things, limit the ability of the Company and its restricted subsidiaries to: (i) incur additional indebtedness, (ii) pay dividends on capital stock or redeem, repurchase or retire the Company’s capital stock or subordinated indebtedness, (iii) transfer or sell assets, (iv) make investments, (v) create certain liens, (vi) enter into agreements that restrict dividends or other payments to the Company from its restricted subsidiaries, (vii) consolidate, merge or transfer all or substantially all of the assets of the Company and its restricted subsidiaries, taken as a whole, (viii) engage in transactions with affiliates, and (ix) create unrestricted subsidiaries.
Outstanding letters of credit		27,800,000		$ 27,800,000
Outstanding borrowings		0		0
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Revolving credit facility							$ 500,000,000
Borrowing base		125,000,000		125,000,000
Available capacity on the Revolving Credit Facility		97,200,000		$ 97,200,000
Minimum [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Commitment fees on unused portion of revolving credit facility				0.375%
Maximum [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Commitment fees on unused portion of revolving credit facility				0.50%
12% Senior Unsecured PIK Notes Due 2018 [Member]
Debt Instrument [Line Items]
Debt instrument interest rate						12.00%
Debt instrument repurchased amount						$ 510,700,000
Debt instrument, outstanding principal balance amount						437,300,000
Debt instrument, premium amount						47,600,000
Debt instrument, accrued interest amount						$ 25,800,000
Debt instrument, unamoritzed discount and deferred financing costs					$ 11,800,000
Loss on extinguishment of debt					(59,400,000)
Amortization of deferred financing costs and debt discount			$ 1,000,000		$ 3,000,000
12% Senior Unsecured PIK Notes Due 2018 [Member] | Maximum [Member]
Debt Instrument [Line Items]
Amortization of deferred financing costs and debt discount		100,000		$ 1,900,000
8.875% Senior Unsecured Notes Due 2023 [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	8.875%
Debt instrument, outstanding principal balance amount	$ 550,000,000
Amortization of deferred financing costs and debt discount		0.8
Issuance date	Jul. 06, 2015
Notes issued percentage price	97.903%
Debt instrument, proceeds	$ 525,500,000
Debt instrument, fair value		$ 442,800,000		$ 442,800,000