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Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 30, 2017
Net income | $ 55,435 | $ 46,718 | $ 133,179 | $ 138,584
Unrealized holding (losses) gains arising during period | (17,036) | 10,874 | (103,389) | 50,961
Non-credit portion of other-than-temporary impairments recognized in other comprehensive income | 0 | 19 | 0 | 23
Amounts reclassified into net income: Held-to-maturity securities | (6) | (35) | (22) | (95)
Amounts reclassified into net income: Non-credit other than temporary impairments | 0 | 25 | 0 | 25
Amounts reclassified into net income: Realized losses (gains) on disposals of available-for-sale securities | 8,563 | (4,394) | 14,424 | (4,638)
Total unrealized (losses) gains on investment securities | (8,479) | 6,489 | (88,987) | 46,276
Amount reclassified into net income: Net actuarial loss | 420 | 329 | 1,260 | 989
Total defined benefit pension and post-retirement plans | 420 | 329 | 1,260 | 989
Other comprehensive (loss) income | (8,059) | 6,818 | (87,727) | 47,265
Comprehensive income | $ 47,376 | $ 53,536 | $ 45,452 | $ 185,849

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