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Principal Amount Of Convertible Debt Sold

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Amount of other increase (decrease) in additional paid in capital (APIC).

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The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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Expiration, mandatory redemption, or due date, in CCYY-MM-DD format, of the financial instrument issued in exchange for the original debt being converted in a noncash or part noncash transaction.

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Dividend or interest rate associated with the financial instrument issued in exchange for the original debt being converted in a noncash or part noncash transaction. Noncash are transactions that affect recognized assets or liabilities but that do not result in cash receipts or cash payments. Part noncash refers to that portion of the transaction not resulting in cash receipts or cash payments.

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The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

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Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

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Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instruments must exceed threshold percentage for a specified number of trading days to trigger conversion feature, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

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Face (par) amount of debt instrument at time of issuance.

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The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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A fee charged for services from professionals such as doctors, lawyers and accountants. The term is often expanded to include other professions, for example, pharmacists charging to maintain a medicinal profile of a client or customer.

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Convertible Senior Notes - Additional Information (Detail) - USD ($)		12 Months Ended
	Dec. 17, 2013	Dec. 31, 2015	Dec. 31, 2014
2018 Convertible Notes [Member]
Debt Disclosure [Line Items]
Estimated aggregate fair value		$ 105,100,000	$ 113,200,000
Principal amount		$ 120,000,000
2.75% Convertible Senior Notes Due 2018 [Member]
Debt Disclosure [Line Items]
Sale of convertible notes, principal amount	$ 120,000,000
Interest rate		2.75%
Conversion rate (shares)		95
Conversion rate, price per $1,000		$ 1,000
Common shares converted value (shares)		11,400,000
Money conversion price per share ($ per share)		$ 10.53
Convertible senior notes maturity date		Dec. 15, 2018
Net proceeds from convertible notes	115,400,000
Professional fee	$ 4,600,000
Additional paid-in capital		$ 13,100,000
Strike price per share ($ per share)		$ 14.03
Threshold percentage of conversion price		130.00%
Convertible senior notes trading price		$ 1,000
Percentage of product of last reported sale price of common stock		98.00%
2.75% Convertible Senior Notes Due 2018 [Member] \| Minimum [Member]
Debt Disclosure [Line Items]
Debt convertible trading days		20 days
Debt convertible consecutive trading days		5 days
2.75% Convertible Senior Notes Due 2018 [Member] \| Maximum [Member]
Debt Disclosure [Line Items]
Debt convertible consecutive trading days		30 days