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PARENT COMPANY STATEMENTS, Condensed Statements of Income (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Expenses [Abstract] |  |  |
Interest on borrowings | $ 3,904 | $ 2,949 | $ 2,537
Acquisition expenses | 25,986 | 1,706 | 7,037
Other expenses | 18,540 | 16,553 | 13,521
Income before tax benefit and equity in undistributed net income of subsidiaries | 159,965 | 154,597 | 132,217
Income tax benefit/(expense) | (9,248) | (50,785) | (40,987)
Net income | 150,717 | 103,812 | 91,230
Other comprehensive (loss), net of tax [Abstract] |  |  |
Changes in other comprehensive income/(loss) related to pension and other post retirement obligations | 168 | 3,322 | (4,567)
Changes in other comprehensive loss related to unrealized losses on available-for-sale securities | (11,065) | (14,714) | (6,918)
Other comprehensive (loss), net of tax | (10,897) | (11,392) | (11,485)
Comprehensive income | 139,820 | 92,420 | 79,745
Parent Company [Member] |  |  |
Dividends from subsidiaries [Abstract] |  |  |
Bank subsidiary | 91,000 | 89,000 | 70,000
Non-bank subsidiaries | 35,500 | 1,750 | 6,000
Interest and dividends on investments | 133 | 102 | 94
Total revenues | 126,633 | 90,852 | 76,094
Expenses [Abstract] |  |  |
Interest on borrowings | 3,904 | 2,949 | 2,537
Acquisition expenses | 91 | 429 | 0
Other expenses | 26 | 11 | 19
Total expenses | 4,021 | 3,389 | 2,556
Income before tax benefit and equity in undistributed net income of subsidiaries | 122,612 | 87,463 | 73,538
Income tax benefit/(expense) | 1,930 | 866 | (572)
Income before equity in undistributed net income of subsidiaries | 124,542 | 88,329 | 72,966
Equity in undistributed net income of subsidiaries | 26,175 | 15,483 | 18,264
Net income | 150,717 | 103,812 | 91,230
Other comprehensive (loss), net of tax [Abstract] |  |  |
Changes in other comprehensive income/(loss) related to pension and other post retirement obligations | 168 | 3,322 | (4,567)
Changes in other comprehensive loss related to unrealized losses on available-for-sale securities | (11,065) | (14,714) | (6,918)
Other comprehensive (loss), net of tax | (10,897) | (11,392) | (11,485)
Comprehensive income | $ 139,820 | $ 92,420 | $ 79,745

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