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Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Net income	$ 72,266	$ 58,819	$ 133,614	$ 77,744
Unrealized holding gains (losses) arising during period	66,002	(18,955)	147,315	(86,353)
Amounts reclassified into net income: Held-to-maturity securities	(17)	(6)	(24)	(16)
Amounts reclassified into net income: Realized (gains) losses on disposals and OTTI of available-for-sale securities	(1,027)	2,267	(1,878)	5,861
Total unrealized gains (losses) on investment securities	64,958	(16,694)	145,413	(80,508)
Amount reclassified into net income: Net actuarial loss	524	420	1,049	840
Total defined benefit pension and post-retirement plans	524	420	1,049	840
Other comprehensive income (loss)	65,482	(16,274)	146,462	(79,668)
Comprehensive income (loss)	$ 137,748	$ 42,545	$ 280,076	$ (1,924)

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