| **Condensed Financial Information (parent company only)**                        | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
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| **Condensed Financial Information of Parent Company Only Disclosure [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| Condensed Financial Information (parent company only)                            | CONDENSED FINANCIAL INFORMATION (parent company only)Presented below is condensed financial information as to financial position, results of operations, and cash flows of the Corporation. Condensed Balance SheetsDecember 31, 2016December 31, 2015Assets  Cash$31,944$43,622Investment in subsidiaries978,291932,372Investment securities18,765Premises and equipment1,2601,361Interest receivable4747Goodwill448448Cash surrender value of life insurance1,0821,041Tax asset, deferred and receivable5212,024Other assets5,2745,195Total assets$1,037,632$986,110Liabilities  Subordinated debentures and term loans$127,427$127,663Interest payable880873Other liabilities7,6687,065Total liabilities135,975135,601Stockholders' equity901,657850,509Total liabilities and stockholders' equity$1,037,632$986,110Condensed Statements of Income and Comprehensive Income December 31, 2016 December 31, 2015 December 31, 2014Income     Dividends from subsidiaries$33,546 $39,032 $53,231Gain on the sale of insurance subsidiary 8,265 Gain on cancellation of subordinated debentures 1,250 Other income143 197 538Total income33,689 48,744 53,769Expenses     Interest expense7,185 6,661 6,616Salaries and employee benefits639 3,023 3,128Net occupancy and equipment expenses832 464 442Other outside services967 1,455 458Professional services279 636 409Other expenses(470) 1,234 1,132Total expenses9,432 13,473 12,185Income before income tax benefit (expense) and equity in undistributed income of subsidiaries24,257 35,271 41,584Income tax benefit (expense)3,243 (974) 3,999Income before equity in undistributed income of subsidiaries27,500 34,297 45,583Equity in undistributed (distributions in excess of) income of subsidiaries53,551 31,087 14,579Net income available to common stockholders$81,051 $65,384 $60,162      Net income$81,051 $65,384 $60,162Other comprehensive income (loss)(12,219) 268 4,780Comprehensive income$68,832 $65,652 $64,942Condensed Statement of Cash Flows Year Ended December 31, 2016 2015 2014Cash Flow From Operating Activities:     Net income$81,051 $65,384 $60,162Adjustments to Reconcile Net Income to Net Cash:     Share-based compensation1,166 843 887Distributions in excess of (equity in undistributed) income of subsidiaries(53,551) (31,087) (14,579)Gain on sale of insurance subsidiary (8,265) Gain on cancellation of subordinated debentures (1,250) Net Change in:     Other assets833 (441) 2,425Other liabilities849 (1,486) 1,466Investment in subsidiaries - operating activities(1,938) 197 (4,517)Net cash provided by operating activities28,410 23,895 45,844Cash Flow From Investing Activities:     Purchase of securities available for sale (19,804)    Net cash paid in acquisition (14,500) (12,832)Proceeds from business divestitures  16,000 Other  575  Net cash provided (used) in investing activities(19,804) 2,075 (12,832)Cash Flow From Financing Activities:     Cash dividends(22,203) (15,654) (10,694)Repayment of borrowings (3,750) Proceeds from issuance of long-term debt  Preferred stock redemption under small business lending fund  Stock issued under employee benefit plans462 460 478Stock issued under dividend reinvestment and stock purchase plan835 661 523Stock options exercised2,602 1,531 564Stock redeemed(1,980) (1,640) (1,067)Net cash used by financing activities(20,284) (18,392) (10,196)Cash, beginning of the year43,622 36,044 13,228Cash, end of year$31,944 $43,622 $36,044 |

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| - Definition
The entire disclosure for condensed financial information, including the financial position, cash flows, and the results of operations of the registrant (parent company) as of the same dates or for the same periods for which audited consolidated financial statements are being presented. Alternatively, the details of this disclosure can be reported by the specific parent company taxonomy elements, indicating the appropriate date and period contexts in an instance document.
+ References
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