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Nature of Business - Tax Effects Related to the Change in Each Component of Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Equity [Abstract] |  |  |
Unrealized gain (loss) on available-for-sale securities, Before-Tax Amount | $ 774 | $ 926 | $ 8,230
Unrealized gain (loss) on available-for-sale securities, Tax (Expense) Benefit | (201) | (241) | (3,210)
Unrealized gain (loss) on available-for-sale securities, Net-of-Tax Amount | 573 | 685 | 5,020
Reclassification adjustment for amounts related to available-for-sale investments included in net income (loss), Before-Tax Amount | (397) | (804) | (4,684)
Reclassification adjustment for amounts related to available-for-sale investments included in net income (loss), Tax (Expense) Benefit | 103 | 209 | 1,827
Reclassification adjustment for amounts related to available-for-sale investments included in net income (loss), Net-of-Tax Amount | (294) | (595) | (2,857)
Reclassification adjustment for amounts reclassed to retained earnings related of the adoption of ASU 2018-02/2016-01, Before-Tax Amount |  | (4,351) |
Reclassification adjustment for amounts reclassed to retained earnings related of the adoption of ASU 2018-02/2016-01, Tax (Expense) Benefit |  | 1,131 |
Reclassification adjustment for amounts reclassed to retained earnings related of the adoption of ASU 2018-02/2016-01, Net-of-Tax Amount |  | (3,220) |
Unrealized gains (losses) on cash flow hedges, Before-Tax Amount |  |  | (897)
Unrealized gains (losses) on cash flow hedges, Tax (Expense) Benefit |  |  | 278
Unrealized gains (losses) on cash flow hedges, Net-of-Tax Amount |  |  | (619)
Reclassification adjustment for amounts related to cash flow hedges included in net income, Before-Tax Amount |  |  | 897
Reclassification adjustment for amounts related to cash flow hedges included in net income, Tax (Expense) Benefit |  |  | (278)
Reclassification adjustment for amounts related to cash flow hedges included in net income, Net-of-Tax Amount |  |  | 619
Defined benefit plan adjustments, Before-Tax Amount | (2,488) | (5,638) | 654
Defined benefit plan adjustments, Tax (Expense) Benefit | 771 | 1,748 | (203)
Defined benefit plan adjustments, Net-of-Tax Amount | (1,717) | (3,890) | 451
Reclassification adjustment for amounts related to defined benefit plan adjustments included in net income (loss), Before-Tax Amount | 771 | 196 | 406
Reclassification adjustment for amounts related to defined benefit plan adjustments included in net income (loss), Tax (Expense) Benefit | (239) | (61) | (126)
Reclassification adjustment for amounts related to defined benefit plan adjustments included in net income (loss), Net-of-Tax Amount | 532 | 135 | 280
Foreign currency translation adjustment, Before-Tax Amount | (1,480) | (4,236) | 5,999
Foreign currency translation adjustment, Net-of-Tax Amount | (1,480) | (4,236) | 5,999
Total Other Comprehensive Income (Loss), Before-Tax Amount | (2,820) | (13,907) | 10,605
Total Other Comprehensive Income (Loss), Tax (Expense) Benefit | 434 | 2,786 | (1,712)
Other Comprehensive Income (Loss), net of tax | $ (2,386) | $ (11,121) | $ 8,893

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