Long-Term Debt and Other Liabilities - Additional Information (Detail) (USD $) Share data in Millions, except Per Share data, unless otherwise specified	0 Months Ended	3 Months Ended		12 Months Ended	0 Months Ended
	Mar. 31, 2015	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Mar. 03, 2015	Nov. 02, 2010
Debt Instrument [Line Items]
Additional paid-in-capital	$ 846,950,000	$ 846,950,000		$ 884,205,000
Proceeds received from the issuance of the convertible notes		361,940,000
Forward stock repurchase transaction, shares	7.2
Total debt	570,529,000	570,529,000		310,252,000
Amortization of deferred financing costs		784,000	836,000
Debt issuance costs	18,008,000	18,008,000		11,296,000
Letters of Credit [Member]
Debt Instrument [Line Items]
Credit facility/letters of credit amount outstanding	7,900,000	7,900,000		7,900,000
Amended and Restated Senior Term Facility [Member]
Debt Instrument [Line Items]
Maturity date		Mar. 21, 2018
Loan origination fees		22,200,000
Total debt	306,702,000	306,702,000		309,244,000
Principal payment		1,700,000
Non lender fees		4,100,000
Amortization of deferred financing costs		700,000	800,000
Debt issuance costs	10,600,000	10,600,000		11,296,000
Percentage used for mandatory prepayment		50.00%
Percentage of prepayment		25.00%
Mandatory prepayment		0		900,000
Voluntary prepayment percentage	3.00%	3.00%
Voluntary prepayment percentage	3.00%	3.00%
Amended and Restated Senior Term Facility [Member] | Maximum [Member]
Debt Instrument [Line Items]
Leverage ratio		3.25
Leverage ratio		2.0
Amended and Restated Senior Term Facility [Member] | Minimum [Member]
Debt Instrument [Line Items]
Leverage ratio		3.25
Leverage ratio		2.0
Amended and Restated Senior Term Facility [Member] | Tranche B-1 Loans [Member]
Debt Instrument [Line Items]
Amount of credit facility agreement	248,000,000	248,000,000
Amended and Restated Senior Term Facility [Member] | Tranche B-1 Loans [Member] | Interest Rate [Member]
Debt Instrument [Line Items]
Interest rate	11.25%	11.25%
Amended and Restated Senior Term Facility [Member] | Tranche B-1 Loans [Member] | London Interbank Offered Rate (LIBOR) [Member] | Interest Rate [Member]
Debt Instrument [Line Items]
Statutory rate floor		1.50%
Libor rate loan margin		9.75%
Amended and Restated Senior Term Facility [Member] | Tranche B-1 Loans [Member] | Base Rate [Member] | Interest Rate [Member]
Debt Instrument [Line Items]
Base rate floor		2.50%
Base rate loan margin		8.75%
Amended and Restated Senior Term Facility [Member] | Tranche B-2 Loans [Member]
Debt Instrument [Line Items]
Amount of credit facility agreement	75,000,000	75,000,000
Amended and Restated Senior Term Facility [Member] | Tranche B-2 Loans [Member] | Interest Rate [Member]
Debt Instrument [Line Items]
Interest rate	7.50%	7.50%
Amended and Restated Senior Term Facility [Member] | Tranche B-2 Loans [Member] | London Interbank Offered Rate (LIBOR) [Member] | Interest Rate [Member]
Debt Instrument [Line Items]
Statutory rate floor		1.00%
Libor rate loan margin		6.50%
Amended and Restated Senior Term Facility [Member] | Tranche B-2 Loans [Member] | Base Rate [Member] | Interest Rate [Member]
Debt Instrument [Line Items]
Base rate floor		2.00%
Base rate loan margin		5.50%
Alaska Facility [Member]
Debt Instrument [Line Items]
Interest rate						10.00%
Amount of credit facility agreement						4,100,000
Total debt	882,000	882,000		1,008,000
Credit facility, termination date		2015-04
Payment period for principal amounts outstanding		6 years
Increase in basis points of revenue share		3.00%
Alaska Facility [Member] | Maximum [Member]
Debt Instrument [Line Items]
Revenue share		100,000	100,000
3.75% Convertible Senior Notes [Member]
Debt Instrument [Line Items]
Principal amount of Convertible Notes	361,900,000	361,900,000			361,900,000
Interest rate					3.75%
Option granted to initial purchasers					60,000,000
Maturity date					Mar. 01, 2020
Additional paid-in-capital					100,000,000
Convertible Notes, carrying amount of liability component	262,945,000	262,945,000			261,900,000
Effective interest rate on convertible notes	11.50%	11.50%
Proceeds received from the issuance of the convertible notes					361,900,000
Convertible Notes, unamortized discount	99,000,000	99,000,000
Conversion rate					41.9274
Principal amount					1,000
Conversion price					$ 23.85
Multiples of principal amount					1,000
Debt instrument redemption price, percentage					100.00%
Forward stock repurchase transactions amount					140,000,000
Forward stock repurchase transaction, shares					7.2
Forward stock repurchase transaction, settlement date					2020-03-01
3.75% Convertible Senior Notes [Member] | Maximum [Member]
Debt Instrument [Line Items]
Common stock price trading days		5
Common stock price consecutive trading days		5 days
Debt instrument redemption price, percentage		98.00%
3.75% Convertible Senior Notes [Member] | Minimum [Member]
Debt Instrument [Line Items]
Percentage of common share price over conversion price for conversion		130.00%
Common stock price trading days		20
Common stock price consecutive trading days		30 days
3.75% Convertible Senior Notes [Member] | Issuance Costs [Member]
Debt Instrument [Line Items]
Additional paid-in-capital	2,900,000	2,900,000
Loan origination fees		10,400,000
Issuance cost recorded to deferred financing costs	7,500,000	7,500,000
3.75% Convertible Senior Notes [Member] | Institutional Buyers [Member]
Debt Instrument [Line Items]
Principal amount of Convertible Notes					340,000,000
3.75% Convertible Senior Notes [Member] | Initial Purchasers [Member]
Debt Instrument [Line Items]
Principal amount of Convertible Notes					$ 21,900,000