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PARENT COMPANY STATEMENTS, Condensed Statements of Income (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Expenses [Abstract] |  |  |
Interest on borrowings | $ 2,949 | $ 2,537 | $ 2,477
Acquisition expenses | 1,706 | 7,037 | 123
Other expenses | 16,553 | 13,521 | 17,310
Income before tax benefit and equity in undistributed net income of subsidiaries | 154,597 | 132,217 | 129,690
Income tax benefit/(expense) | (50,785) | (40,987) | (38,337)
Net income | 103,812 | 91,230 | 91,353
Other comprehensive (loss)/income, net of tax [Abstract] |  |  |
Other comprehensive income/(loss) related to pension and other post retirement obligations | 3,322 | (4,567) | (9,571)
Other comprehensive (loss)/income related to unrealized (losses)/gains on available-for-sale securities | (14,714) | (6,918) | 66,837
Other comprehensive (loss)/income, net of tax | (11,392) | (11,485) | 57,266
Comprehensive income | 92,420 | 79,745 | 148,619
Parent Company [Member] |  |  |
Dividends from subsidiaries [Abstract] |  |  |
Bank subsidiary | 89,000 | 70,000 | 57,200
Non-bank subsidiaries | 1,750 | 6,000 | 3,900
Interest and dividends on investments | 102 | 94 | 88
Total revenues | 90,852 | 76,094 | 61,188
Expenses [Abstract] |  |  |
Interest on borrowings | 2,949 | 2,537 | 2,477
Acquisition expenses | 429 | 0 | 0
Other expenses | 11 | 19 | 37
Total expenses | 3,389 | 2,556 | 2,514
Income before tax benefit and equity in undistributed net income of subsidiaries | 87,463 | 73,538 | 58,674
Income tax benefit/(expense) | 866 | (572) | 581
Income before equity in undistributed net income of subsidiaries | 88,329 | 72,966 | 59,255
Equity in undistributed net income of subsidiaries | 15,483 | 18,264 | 32,098
Net income | 103,812 | 91,230 | 91,353
Other comprehensive (loss)/income, net of tax [Abstract] |  |  |
Other comprehensive income/(loss) related to pension and other post retirement obligations | 3,322 | (4,567) | (9,571)
Other comprehensive (loss)/income related to unrealized (losses)/gains on available-for-sale securities | (14,714) | (6,918) | 66,837
Other comprehensive (loss)/income, net of tax | (11,392) | (11,485) | 57,266
Comprehensive income | $ 92,420 | $ 79,745 | $ 148,619

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