Accounting for Income Taxes - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Income Taxes [Line Items]
Provision for income taxes	$ 15,113	$ 11,149	$ 27,474	$ 22,444
Effective income tax rate, continuing operations	23.20%	26.20%	23.20%	24.90%
Valuation allowance, deferred tax asset	$ 31,700		$ 31,700
Unrecognized tax benefits	$ 42,600		$ 42,600		$ 39,400
Tax Holiday effect		$ 8,200
Tax holiday effect on diluted earnings per share	$ 0.11	$ 0.10	$ 0.21	$ 0.20
Foreign Tax Authority [Member]
Income Taxes [Line Items]
Foreign income tax rate			30.00%	30.00%
Tax Holiday effect	$ 8,600		$ 17,200	$ 16,400

Effective Income Tax Rate Reconciliation, Tax Holiday, Effect on Diluted Earnings Per Share

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- Definition

Effective Income Tax Reconciliation, at Foreign Income Tax Rate

+ References

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Income Taxes [Line Items]

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32537-109319

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32698-109319

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Subparagraph (a),(b)
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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6515339

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income exempt from income tax because of a tax holiday.

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Amount of unrecognized tax benefits.

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