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Consolidation Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Net income	$ 168,826	$ 158,495	$ 165,861
Unrealized holding gains (losses) arising during year	43,015	(5,977)	(26,143)
Non-credit portion of other-than-temporary impairments recognized in other comprehensive income	23	(6)	0
Amounts reclassified into net income: Held-to-maturity securities	(116)	(92)	(377)
Amounts reclassified into net income: Non-credit other-than-temporary impairment	68	138	232
Amounts reclassified into net income: Realized losses (gains) on available for sale securities	(4,537)	3,064	(9,110)
Total unrealized gains (losses) on investment securities	38,453	(2,873)	(35,398)
Net actuarial (loss) gain	(3,700)	(7,852)	1,585
Amounts reclassified into net income: Net actuarial loss	1,367	4,200	4,600
Total defined benefit pension and post-retirement plans	(2,333)	(3,652)	6,185
Other comprehensive income (loss)	36,120	(6,525)	(29,213)
Comprehensive income	$ 204,946	$ 151,970	$ 136,648

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Net of tax amount of the reclassification adjustment related to held-to-maturity securities transferred from the available-for-sale category. This amount includes amortization and amounts realized from the disposal of these securities.

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