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Income Taxes - Additional Information (Detail) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Income Tax Contingency [Line Items] |  |  |  |
Federal income tax rate | 35.00% | 35.00% | 35.00% |
Valuation allowances | $ 4,066,000 | $ 3,773,000 |  |
Research and development, tax credit | 1,100,000 | 1,500,000 | $ 1,800,000 |
Investment tax credits | 2,200,000 |  |  |
Unremitted earnings, reinvested | 399,900,000 | 338,600,000 |  |
Deferred tax liability | 0 |  |  |
Gross unrecognized tax benefits | 14,200,000 | $ 12,200,000 | $ 14,900,000 | $ 14,900,000
Unrecognized tax benefits that would impact effective tax rate | 11,300,000 |  |  |
Minimum [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Gross unrecognized tax benefits balance may decrease within the next twelve months | 0 |  |  |
Maximum [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Gross unrecognized tax benefits balance may decrease within the next twelve months | 900,000 |  |  |
United States - Federal [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Net operating loss carryforwards | $ 15,500,000 |  |  |
Net operating loss carryforwards expiration year | 2036 |  |  |
Tax credit carryforwards | $ 2,900,000 |  |  |
Tax credit carryforwards expiration year | 2035 |  |  |
United States - State [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Net operating loss carryforwards | $ 77,800,000 |  |  |
Tax credit carryforwards | $ 200,000 |  |  |
Tax credit carryforwards expiration year | 2017 |  |  |
United States - State [Member] | Minimum [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Net operating loss carryforwards expiration year | 2017 |  |  |
United States - State [Member] | Maximum [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Net operating loss carryforwards expiration year | 2036 |  |  |
Foreign Tax Authority [Member] |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Net operating loss carryforwards | $ 4,800,000 |  |  |
Net operating loss carryforwards expiration year | 2019 |  |  |
Tax credit carryforwards | $ 800,000 |  |  |
Tax credit carryforwards expiration year | 2030 |  |  |

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- Definition Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (d)(3) -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32718-109319 + Details
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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32687-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 6.I) -URI http://asc.fasb.org/extlink&oid=34349781&loc=d3e330036-122817 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32698-109319 + Details
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- Definition The amount deducted from an entities' taxes, reflecting a percentage of an amount invested in certain assets spread over the useful life of those assets; includes deferred investment tax credits. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585 + Details
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