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Debt - Additional Information (Detail) - USD ($) |  |  | 9 Months Ended |
--- | --- | --- | --- | ---
Jun. 27, 2019 | Jun. 26, 2019 | Sep. 30, 2019 | Dec. 31, 2018
Debt Instrument [Line Items] |  |  |  |
Maximum percentage of stock of non US subsidiaries pledge to secure obligation |  |  | 66.00% |
Amended credit agreement, debt issuance costs |  |  | $ 1,278,000 |
Federal Funds Rate | Minimum |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate |  |  | 0.50% |
Federal Funds Rate | Maximum |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate |  |  | 1.90% |
London Interbank Offered Rate |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate |  |  | 2.02% |
Revolving Note (U.S. Dollar) |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Undrawn borrowing capacity |  |  | $ 385,129,000 |
United State Bank Of America Credit Facility |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate |  |  | 5.00% |
Euro Currency Rate Loans | Minimum |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate |  |  | 0.00% |
Euro Currency Rate Loans | Minimum | Credit Agreement |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate |  |  | 1.25% |
Euro Currency Rate Loans | Maximum |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate |  |  | 1.00% |
Euro Currency Rate Loans | Maximum | Credit Agreement |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate |  |  | 2.25% |
Base Rate Loans | Minimum | Credit Agreement |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate |  |  | 0.25% |
Base Rate Loans | Maximum | Credit Agreement |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest rate |  |  | 1.25% |
DEG Loan |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Semi-annual principal payments earliest date |  |  | 2015-03 |
Semi-annual principal payments latest date |  |  | 2019-09 |
DEG Vietnam Loan |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Semi-annual principal payments earliest date |  |  | 2017-11 |
Semi-annual principal payments latest date |  |  | 2023-05 |
Revolving Credit Facility | Revolving Note (U.S. Dollar) |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Maximum borrowing capacity | $ 475,000,000 | $ 350,000,000 |  | $ 350,000,000
Maximum borrowing capacity increase subject to specified conditions |  |  | $ 175,000,000 |
Debt maturity date | Jun. 27, 2024 | Mar. 17, 2021 |  |

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