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PARENT COMPANY STATEMENTS, Condensed Statements of Income (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Expenses [Abstract] |  |  |
Interest on borrowings | $ 3,898 | $ 4,677 | $ 3,904
Acquisition expenses | 8,608 | (769) | 25,986
Loss on debt prepayment | 0 | 318 | 0
Other expenses | 24,090 | 21,471 | 22,609
Income before tax benefit and equity in undistributed net income of subsidiaries | 209,338 | 212,988 | 159,965
Income tax benefit | (40,275) | (44,347) | (9,248)
Net income | 169,063 | 168,641 | 150,717
Other comprehensive income/(loss), net of tax [Abstract] |  |  |
Changes in other comprehensive (loss)/income related to pension and other post retirement obligations | (2,045) | (11,204) | 168
Changes in other comprehensive income/(loss) related to unrealized losses on available-for-sale securities | 37,124 | (30,402) | (11,065)
Other comprehensive income/(loss) | 35,079 | (41,398) | (10,897)
Comprehensive income | 204,142 | 127,035 | 139,820
Parent Company [Member] |  |  |
Dividends from subsidiaries [Abstract] |  |  |
Bank subsidiary | 115,000 | 98,000 | 91,000
Non-bank subsidiaries | 27,600 | 9,250 | 35,500
Interest and dividends on investments | 134 | 161 | 133
Total revenues | 142,734 | 107,411 | 126,633
Expenses [Abstract] |  |  |
Interest on borrowings | 4,244 | 4,677 | 3,904
Acquisition expenses | 1,248 | 0 | 91
Loss on debt prepayment | 0 | 318 | 0
Other expenses | 477 | 131 | 26
Total expenses | 5,969 | 5,126 | 4,021
Income before tax benefit and equity in undistributed net income of subsidiaries | 136,765 | 102,285 | 122,612
Income tax benefit | 4,545 | 1,330 | 1,930
Income before equity in undistributed net income of subsidiaries | 141,310 | 103,615 | 124,542
Equity in undistributed net income of subsidiaries | 27,753 | 65,026 | 26,175
Net income | 169,063 | 168,641 | 150,717
Other comprehensive income/(loss), net of tax [Abstract] |  |  |
Changes in other comprehensive (loss)/income related to pension and other post retirement obligations | (2,045) | (11,204) | 168
Changes in other comprehensive income/(loss) related to unrealized losses on available-for-sale securities | 37,124 | (30,402) | (11,065)
Other comprehensive income/(loss) | 35,079 | (41,606) | (10,897)
Comprehensive income | $ 204,142 | $ 127,035 | $ 139,820

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