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Stockholders' Equity - Changes in Accumulated Other Comprehensive Loss, Net of Tax by Component (Detail) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Beginning Balance | $ 363,715 | $ 443,547 | $ 380,426 | $ 446,279
Other comprehensive income (loss) before reclassifications | 2,780 | 713 | 199 | (216)
Amounts reclassified from accumulated other comprehensive income (loss) | (317) | 77 | 872 | 152
Amounts reclassified to retained earnings |  |  |  | 385
Net current period other comprehensive income (loss) | 2,463 | 790 | 1,071 | 321
Ending Balance | 364,194 | 445,975 | 364,194 | 445,975
ASU 2018-02 [Member] |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Beginning Balance | 385 | 385 | 385 |
Amounts reclassified to retained earnings |  |  |  | 385
Net current period other comprehensive income (loss) |  |  |  | 385
Ending Balance | 385 | 385 | 385 | 385
Unrealized Gains (Losses) on Available-for-Sale Securities [Member] |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Beginning Balance | (167) | (378) | (284) | (563)
Other comprehensive income (loss) before reclassifications | 881 | 180 | (50) | 411
Amounts reclassified from accumulated other comprehensive income (loss) | (508) | (73) | 540 | (119)
Net current period other comprehensive income (loss) | 373 | 107 | 490 | 292
Ending Balance | 206 | (271) | 206 | (271)
Defined Benefit Plan Adjustments [Member] |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Beginning Balance | (9,085) | (7,920) | (9,226) | (8,041)
Amounts reclassified from accumulated other comprehensive income (loss) | 191 | 150 | 332 | 271
Net current period other comprehensive income (loss) | 191 | 150 | 332 | 271
Ending Balance | (8,894) | (7,770) | (8,894) | (7,770)
Foreign Currency Adjustments [Member] |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Beginning Balance | (8,942) | (6,972) | (7,292) | (5,812)
Other comprehensive income (loss) before reclassifications | 1,899 | 533 | 249 | (627)
Net current period other comprehensive income (loss) | 1,899 | 533 | 249 | (627)
Ending Balance | (7,043) | (6,439) | (7,043) | (6,439)
Accumulated Other Comprehensive Income [Member] |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |
Beginning Balance | (17,809) | (14,885) | (16,417) | (14,416)
Ending Balance | $ (15,346) | $ (14,095) | $ (15,346) | $ (14,095)

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