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Consolidation Statements of Comprehensive Income - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Net income | $ 271,623 | $ 178,939 | $ 168,826
Unrealized holding gains (losses) arising during year | 168,021 | (97,284) | 43,015
Non-credit portion of other-than-temporary impairments recognized in other comprehensive income | 0 | 0 | 23
Amounts reclassified into net income: Held-to-maturity securities | (46) | 87 | (116)
Amounts reclassified into net income: Non-credit other-than-temporary impairment | 0 | 0 | 68
Amounts reclassified into net income: Realized losses (gains) on available for sale securities | 530 | 31,316 | (4,537)
Total unrealized gains (losses) on investment securities | 168,505 | (65,881) | 38,453
Net actuarial loss | (10,898) | (8,906) | (3,700)
Amounts reclassified into net income: Net actuarial loss | 2,099 | 1,680 | 1,367
Total defined benefit pension and post-retirement plans | (8,799) | (7,226) | (2,333)
Other comprehensive income (loss) | 159,706 | (73,107) | 36,120
Comprehensive income | $ 431,329 | $ 105,832 | $ 204,946

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