Company's Debt Maturities on Calendar Year Basis (Detail) - USD ($) $ in Thousands		Dec. 31, 2018		Dec. 31, 2017
Debt Instrument [Line Items]
Total		$ 679,967
2019		54,263
2020		61,977
2021		61,977
2022		163,692
2023		90,769
Thereafter		247,289
Senior Secured Notes
Debt Instrument [Line Items]
Total		365,481		$ 408,174
2019		42,693
2020		42,693
2021		42,693
2022		42,693
2023		42,693
Thereafter		152,016
Convertible Notes | 5.75% Senior Subordinated Notes Due August 2023
Debt Instrument [Line Items]
Total	[1],[2]	48,076
2023	[2]	48,076
Variable Funding Notes
Debt Instrument [Line Items]
Total		95,273	[3]	$ 91,363
Thereafter	[3]	95,273
Senior Secured Term Loan
Debt Instrument [Line Items]
Total	[4]	171,137
2019	[4]	11,570
2020	[4]	19,284
2021	[4]	19,284
2022	[4]	$ 120,999

[1] On February 22, 2018, the Company exchanged $125 million of aggregate principal amount of 1.50% Convertible Notes for $125 million of aggregate principal amount of 5.75% Convertible Notes. See below for further details.

[2] Reflects the debt carrying amount which is accounted for under the Fair Value Option in the consolidated balance sheet as of December 31, 2018. The actual principal outstanding balance of the 5.75% Convertible Notes is $109.7 million as of December 31, 2018.

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

[4] Reflects the net debt carrying amount, effected by the outstanding balance of the original issue discount, in the consolidated balance sheet as of December 31, 2018. The actual principal outstanding balance of the Senior Secured Term Loan is $189.4 million as of December 31, 2018.