Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Consolidated Statements of Comprehensive Income
Net income	$ 230,178	$ 213,780	$ 216,672
Net unrealized (losses) gains on pensions and other benefits	(3,354)	8,986	(16,648)
Net unrealized (losses) gains on securities available for sale	(34,852)	(9,573)	11,806
Net unrealized gains (losses) on cash flow derivative hedges	1,454	785	(850)
Other comprehensive (loss) income	(36,752)	198	(5,692)
Total comprehensive income	$ 193,426	$ 213,978	$ 210,980