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Summary of Significant Accounting Policies and Basis of Presentation - Additional Information (Detail) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 USD ($) Customer | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($)
Accounting Policies [Line Items] |  |  |  |
Amount reclassified from prepaid expenses and other assets to other non-current assets |  | $ 4,390,000 |  |
Cash and cash equivalents | $ 103,172,000 | 177,187,000 | $ 144,479,000 | $ 85,700,000
Depreciation expense | 32,224,000 | 24,873,000 | 18,399,000 |
Impairment of goodwill | 0 | 0 | 0 |
Share based compensation expense | 12,727,000 | 8,147,000 | 12,316,000 |
Related deferred tax benefit | 3,955,000 | 4,508,000 |  |
Stock options outstanding under the 1993,1997, 2006 and 2011 Stock Option Plans |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Related deferred tax benefit | 4,339,000 | 2,891,000 | 3,787,000 |
Production tooling |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Reimbursable tooling capitalized within prepaid expenses and other current assets | $ 6,994,000 | 5,604,000 |  |
Minimum |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Payment terms of contracts | 30 days |  |  |
Minimum | Production tooling |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Property plant and equipment, estimated useful life | 2 years |  |  |
Maximum |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Payment terms of contracts | 120 days |  |  |
Maximum | Production tooling |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Property plant and equipment, estimated useful life | 7 years |  |  |
Patents |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Amortization of intangibles | $ 12,425,000 | $ 12,675,000 | $ 12,751,000 |
Concentration of Credit Risk | Accounts receivable | Lear |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Concentration risk percentage | 24.00% | 25.00% |  |
Concentration of Credit Risk | Accounts receivable | Adient |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Concentration risk percentage | 20.00% | 24.00% |  |
Concentration of Credit Risk | Accounts receivable | Magna |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Concentration risk percentage | 7.00% |  |  |
Concentration of Credit Risk | Accounts receivable | Faurecia |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Concentration risk percentage |  | 7.00% |  |
Customer Concentration Risk | Sales Revenue |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Number of largest customer | Customer | 3 |  |  |
Customer Concentration Risk | Sales Revenue | Lear |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Concentration risk percentage | 20.00% | 21.00% | 22.00% |
Revenues from sales | $ 192,756,000 |  |  |
Customer Concentration Risk | Sales Revenue | Adient |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Concentration risk percentage | 18.00% | 21.00% | 23.00% |
Revenues from sales | $ 173,964,000 |  |  |
Customer Concentration Risk | Sales Revenue | Bosch |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Concentration risk percentage | 8.00% | 8.00% | 9.00% |
Revenues from sales | $ 75,370,000 |  |  |
Foreign Jurisdictions |  |  |  |
Accounting Policies [Line Items] |  |  |  |
Cash and cash equivalents | $ 88,440,000 | $ 162,881,000 |  |

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