Company's Debt Maturities on Calendar Year Basis (Detail) - USD ($) $ in Thousands		Mar. 31, 2018		Dec. 31, 2017
Debt Instrument [Line Items]
Total		$ 769,722
April 1 through December 31, 2018		34,913
2019		54,263
2020		154,271
2021		61,977
2022		160,135
Thereafter		304,163
Senior Secured Notes
Debt Instrument [Line Items]
Total		397,500		$ 408,174
April 1 through December 31, 2018		32,020
2019		42,693
2020		42,693
2021		42,693
2022		42,693
Thereafter		194,708
Convertible Notes | 5.75% Senior Subordinated Notes Due August 2023
Debt Instrument [Line Items]
Total	[1],[2]	109,455
Thereafter	[2]	109,455
Variable Funding Notes
Debt Instrument [Line Items]
Total		92,294	[3]	$ 91,363
2020	[3]	92,294
2017 Senior Secured Term Loan
Debt Instrument [Line Items]
Total	[4]	170,473
April 1 through December 31, 2018	[4]	2,893
2019	[4]	11,570
2020	[4]	19,284
2021	[4]	19,284
2022	[4]	$ 117,442

[1] On February 12, 2018, the Company entered into the Exchange Agreements and consummated the Note Exchange on February 22, 2018, pursuant to which the Company exchanged approximately $125.0 million aggregate principal amount of its 1.50% Convertible Notes for 5.75% Convertible Notes issued by the Company in an aggregate principal amount of approximately $125.0 million. See below for further details.

[2] Reflects the debt carrying amount which is accounted for under the Fair Value Option in the unaudited condensed consolidated balance sheet as of March 31, 2018. The actual principal outstanding balance of the 5.75% Convertible Notes is $116.2 million as of March 31, 2018.

[3] Reflects the net debt carrying amount, effected by the outstanding balance of the original issue discount, in the unaudited condensed consolidated balance sheet as of March 31, 2018. The actual principal outstanding balance of the Variable Funding Notes is $100.0 million as of March 31, 2018.

[4] Reflects the net debt carrying amount, effected by the outstanding balance of the original issue discount, in the unaudited condensed consolidated balance sheet as of March 31, 2018. The actual principal outstanding balance of the Senior Secured Term Loan is $192.3 million as of March 31, 2018.