Long-Term Obligations - Schedule of Long-Term Obligations (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Jan. 29, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Capital leases and other long-term obligations	$ 3,640		$ 3,996
Long-term obligations	179,654		188,689
Long-term obligations	179,654		188,689
Less current portion	(4,175)		(3,671)
Long-term obligations, net of current portion	175,479		185,018
2015 Senior Secured Credit Facilities Due 2018 [Member]
Debt Instrument [Line Items]
Long-term obligations	87,500		89,750
Debt issuance costs	(2,157)		(3,406)
6.25% Convertible Notes Due 2018 [Member]
Debt Instrument [Line Items]
Convertible notes	94,000		104,000
Debt instrument unamortized discount	(2,753)	$ (250)	(4,641)
Debt issuance costs	(576)		$ (1,010)
Long-term obligations	91,247
Long-term obligations	$ 91,247

Capital lease obligation and other long term obligations.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of a written promise to pay a note, initially due after one year or beyond the operating cycle if longer, which can be exchanged for a specified amount of one or more securities (typically common stock), at the option of the issuer or the holder.

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Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after accumulated amortization, of debt discount.

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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