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Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
Net income | $ 58,819 | $ 41,426 | $ 77,744 | $ 91,866
Unrealized holding (losses) gains arising during period | (18,955) | 23,326 | (86,353) | 40,087
Non-credit portion of other-than-temporary impairments recognized in other comprehensive income | 0 | 4 | 0 | 4
Amounts reclassified into net income: Held-to-maturity securities | (6) | (28) | (16) | (60)
Amounts reclassified into net income: Realized losses (gains) on disposals of available-for-sale securities | 2,267 | (1,225) | 5,861 | (244)
Total unrealized (losses) gains on investment securities | (16,694) | 22,077 | (80,508) | 39,787
Amount reclassified into net income: Net actuarial loss | 420 | 330 | 840 | 660
Total defined benefit pension and post-retirement plans | (420) | (330) | (840) | (660)
Other comprehensive (loss) income | (16,274) | 22,407 | (79,668) | 40,447
Comprehensive income (loss) | $ 42,545 | $ 63,833 | $ (1,924) | $ 132,313

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