Stock Based Compensation - Additional Information (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock option expense	$ 36	$ 57
Amortization of non-vested stock grants	$ 1,193	$ 596
Stock options exercised by employees	1,500	107,645
Number of shares of non-vested stock that vested	9,880	10,982

Adjustments To Additional Paid In Capital Earned portion of non-vested stock.

No definition available.

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Number of share options (or share units) exercised during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

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-Name Accounting Standards Codification

-Topic 505

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-Section S99

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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

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