Income Taxes - Schedule of Net Operating Losses for Tax Purposes (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2014
Income Tax Disclosure [Abstract]
December 31, 2013	$ (140,959)
U.S. GAAP pretax income	59,142
Income tax differences:
Temporary	627
Permanent	(20,507)
September 30, 2014	$ (101,697)

The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h)(1)(i))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32559-109319

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- Definition

Permanent differences are primarily comprised of the difference between stock based compensation amounts recognized for tax purposes at the time options are exercised (at the intrinsic value) or restricted stock is vested (at fair value of the share price) and previously expensed at the date of grant for US GAAP purposes at then recorded fair values.

+ References

No definition available.

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Temporary differences are primarily comprised of the difference between recognizing expenses for tax purposes associated with rent, compensation and depreciation of fixed assets and US GAAP purposes.

+ References

No definition available.

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