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Income Taxes - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jan. 01, 2018 | Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Income Taxes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Income tax holiday amount |  |  |  |  |  |  |  |  |  | $ 28,000 | $ 25,000 | $ 23,000
Income tax holiday per share benefit |  |  |  |  |  |  |  |  |  | $ 0.36 | $ 0.31 | $ 0.29
Effective income tax rate |  |  |  |  |  |  |  |  |  | 13.00% | 96.80% | 13.10%
2017 Tax Act |  |  |  |  |  |  |  |  |  |  | $ 550,000 |
2017 Tax Act, Transition tax |  |  |  |  |  |  |  |  |  |  | 490,000 |
2017 Tax Act, State income taxes and foreign withholding taxes |  |  |  |  |  |  |  |  |  |  | 40,000 |
2017 Tax Act, Remeasurement of deferred taxes |  |  |  |  |  |  |  |  |  |  | $ 20,000 |
Statutory tax rate |  |  |  |  |  |  |  |  |  |  | 21.00% | 35.00%
Net income per diluted common share |  | $ 2.46 | $ 1.83 | $ 1.98 | $ 1.40 | $ (4.44) | $ 1.69 | $ 1.63 | $ 1.31 | $ 7.65 | $ 0.25 | $ 6.41
Effective income tax rate |  |  |  |  |  |  |  |  |  |  | 11.00% |
Net additions for tax positions taken during the prior period |  |  |  |  |  |  |  |  |  | $ 17,651 |  |
Incremental income tax provision |  | $ 12,654 | $ 28,216 | $ 18,884 | $ 28,598 | $ 578,910 | $ 17,696 | $ 16,250 | $ 7,930 | 88,352 | $ 620,786 | $ 78,611
Effect of stock-based compensation |  |  |  |  |  |  |  |  |  | 9,089 | 19,566 |
Release of valuation allowance |  |  |  |  |  |  |  |  |  |  |  | $ (3,000)
Percentage point in effective tax rate related to valuation allowance on certain net operating loss carryforwards |  |  |  |  |  |  |  |  |  |  |  | (0.7)
Valuation allowances |  | 53,893 |  |  |  | 62,098 |  |  |  | 53,893 | 62,098 |
Deferred tax assets, net of valuation allowance |  | 81,886 |  |  |  | $ 79,165 |  |  |  | 81,886 | $ 79,165 |
Tax benefit related to stock option plan |  |  |  |  |  |  |  |  |  |  |  | $ 13,844
Accounting Standards Update 2016-16 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Income Taxes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Retained earnings | $ 4,000 |  |  |  |  |  |  |  |  |  |  |
Foreign net operating losses and credits [Member] |  |  |  |  |  |  |  |  |  |  |  |
Income Taxes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Gross foreign net operating losses |  | 240,000 |  |  |  |  |  |  |  | 240,000 |  |
Valuation allowances |  | 51,000 |  |  |  |  |  |  |  | 51,000 |  |
Deferred tax assets, net of valuation allowance |  | 12,000 |  |  |  |  |  |  |  | $ 12,000 |  |
Change in statutory tax rate [Member] |  |  |  |  |  |  |  |  |  |  |  |
Income Taxes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
2017 Tax Act, change in foreign currency exchange rates on earnings, percentage |  |  |  |  |  |  |  |  |  | (0.02) |  |
GILTI tax [Member] |  |  |  |  |  |  |  |  |  |  |  |
Income Taxes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
2017 Tax Act, change in foreign currency exchange rates on earnings, percentage |  |  |  |  |  |  |  |  |  | 0.020 |  |
Change in Indefinite Reinvestment Assertion for Investments in Foreign Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |  |
Income Taxes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
2017 Tax Act, change in foreign currency exchange rates on earnings, percentage |  |  |  |  |  |  |  |  |  | 0.006 |  |
Stock Based Compensation Tax Benefit [Member] |  |  |  |  |  |  |  |  |  |  |  |
Income Taxes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Net income per diluted common share |  |  |  |  |  |  |  |  |  | $ 0.11 | $ 0.24 |
2017 Tax Act [Member] |  |  |  |  |  |  |  |  |  |  |  |
Income Taxes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Net income per diluted common share |  |  |  |  |  |  |  |  |  |  | $ (6.82) |
Reduction in provisional accrual for federal, state and foreign taxes |  |  |  |  |  |  |  |  |  | $ (24,000) |  |
Net additions for tax positions taken during the prior period |  |  |  |  |  |  |  |  |  | 17,651 |  |
Incremental income tax provision |  |  |  |  |  |  |  |  |  | (6,000) |  |
2017 Tax Act [Member] | Foreign Currency Translation Adjustment [Member] |  |  |  |  |  |  |  |  |  |  |  |
Income Taxes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Incremental income tax provision |  |  |  |  |  |  |  |  |  | 7,000 |  |
Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |
Income Taxes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Expected change in unrecognized tax benefits in the next twelve months |  | $ (1,000) |  |  |  |  |  |  |  | $ (1,000) |  |
United States [Member] |  |  |  |  |  |  |  |  |  |  |  |
Income Taxes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Statutory tax rate |  |  |  |  |  |  |  |  |  | 21.00% |  |
Ireland [Member] |  |  |  |  |  |  |  |  |  |  |  |
Income Taxes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Statutory tax rate |  |  |  |  |  |  |  |  |  | 12.50% |  |
U.K [Member] |  |  |  |  |  |  |  |  |  |  |  |
Income Taxes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Statutory tax rate |  |  |  |  |  |  |  |  |  | 19.00% |  |
Singapore [Member] |  |  |  |  |  |  |  |  |  |  |  |
Income Taxes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Statutory tax rate |  |  |  |  |  |  |  |  |  | 17.00% |  |
Singapore [Member] | Contractual Tax Rate Singapore [Member] |  |  |  |  |  |  |  |  |  |  |  |
Income Taxes [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Marginal effective income tax rate |  |  |  |  |  |  |  |  |  | 0.00% |  |

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- Definition 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 other deductions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319 + Details
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- Definition The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319 + Details
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- Definition Amount of income tax expense from transition tax on accumulated earnings of controlled foreign corporation deemed repatriated pursuant to Tax Cuts and Jobs Act. + References No definition available. + Details
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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