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Stockholders' Equity - Changes in Accumulated Other Comprehensive Loss, Net of Tax by Component (Detail) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2020 | Mar. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |
Beginning Balance | $ 380,426 | $ 446,279
Other comprehensive income (loss) before reclassifications | (2,581) | (929)
Amounts reclassified from accumulated other comprehensive income (loss) | 1,189 | 75
Amounts reclassified to retained earnings |  | 385
Net current period other comprehensive income (loss) | (1,392) | (469)
Ending Balance | 363,715 | 443,547
ASU 2018-02 [Member] |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |
Beginning Balance | 385 |
Amounts reclassified to retained earnings |  | 385
Net current period other comprehensive income (loss) |  | 385
Ending Balance | 385 | 385
Unrealized Gains (Losses) on Available-for-Sale Securities [Member] |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |
Beginning Balance | (284) | (563)
Other comprehensive income (loss) before reclassifications | (931) | 231
Amounts reclassified from accumulated other comprehensive income (loss) | 1,048 | (46)
Net current period other comprehensive income (loss) | 117 | 185
Ending Balance | (167) | (378)
Defined Benefit Plan Adjustments [Member] |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |
Beginning Balance | (9,226) | (8,041)
Amounts reclassified from accumulated other comprehensive income (loss) | 141 | 121
Net current period other comprehensive income (loss) | 141 | 121
Ending Balance | (9,085) | (7,920)
Foreign Currency Adjustments [Member] |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |
Beginning Balance | (7,292) | (5,812)
Other comprehensive income (loss) before reclassifications | (1,650) | (1,160)
Net current period other comprehensive income (loss) | (1,650) | (1,160)
Ending Balance | (8,942) | (6,972)
Accumulated Other Comprehensive Income [Member] |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |
Beginning Balance | (16,417) | (14,416)
Ending Balance | $ (17,809) | $ (14,885)

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