Amount of decrease in additional paid in capital (APIC) resulting from direct costs associated with issuing stock. Includes, but is not limited to, legal and accounting fees and direct costs associated with stock issues under a shelf registration.

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-Name Accounting Standards Codification

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Expense related to distribution, servicing and underwriting fees.

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The cash inflow associated with the amount received from entity's raising of capital via private rather than public placement.

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

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Price of a single share of a number of saleable stocks of a company.

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Number of new stock issued during the period.

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-Name Regulation S-X (SX)

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-Section 04

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Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

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The cash inflow from the additional capital contribution to the entity, net of the cash outflows for costs incurred directly with the issuance of an equity security.

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Shareholders' Equity - Additional Information (Details) (USD $) In Thousands, except Share data, unless otherwise specified	0 Months Ended	1 Months Ended	3 Months Ended
	Mar. 26, 2014	Jan. 31, 2015	Mar. 31, 2015	Mar. 31, 2014	Mar. 26, 2014
Schedule of Capitalization, Equity [Line Items]
Securities purchase agreements, shares	972,004	4,312,500
Price per share of common stock	$ 25.72us-gaap_SharePrice	$ 27.00us-gaap_SharePrice			$ 25.72us-gaap_SharePrice
Proceeds from issuance of shares in a public offering, net of issuance costs		$ 110,041	$ 110,041	$ 0
Underwriting discounts and commissions		6,086
Offering expenses capitalized by the Company		311
Securities purchase agreements gross proceed	25,000		0	25,000
Securities purchase agreements, value			110,041
Affiliates of Third Security
Schedule of Capitalization, Equity [Line Items]
Securities purchase agreements, shares	243,001	555,556
Securities purchase agreements, value	$ 6,250
Overallotment Option Exercise By Underwriters
Schedule of Capitalization, Equity [Line Items]
Securities purchase agreements, shares		562,500