Long-Term Obligations (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Long-term Debt, Fiscal Year Maturity [Abstract]
2014	$ 3,232
2015	135,652
2016	241
2017	255
2018	70,271
Thereafter	623,291
Total long-term obligations	832,942	$ 704,155
Trust Preferred Securities	121,500
Junior Subordinated Debt [Member]
Long-term Debt, Fiscal Year Maturity [Abstract]
Total long-term obligations	125,259
Junior Subordinated Debt [Member] \| Junior Subordinanted Debenture at 3 Month Libor Plus 1.75% Maturing June 30, 2036 [Member]
Long-term Debt, Fiscal Year Maturity [Abstract]
Total long-term obligations	90,207	96,392
Junior Subordinated Debt [Member] \| Junior Subordinated Debenture At 3 Month Libor Plus 2 Point 25 Percent Maturing June 15 2034 [Member] [Member]
Long-term Debt, Fiscal Year Maturity [Abstract]
Total long-term obligations	24,742	25,774
Junior Subordinated Debt [Member] \| Junior Subordinated Debenture At 3 Month Libor Plus 2 Point 85 Percent Maturing April 7 2034 [Member] [Member]
Long-term Debt, Fiscal Year Maturity [Abstract]
Total long-term obligations	$ 10,310	10,310
Subordinated Debt [Member] \| Subordinated Notes Payable At 5 Point 125 Percent Maturing June 1 2015 [Member]
Debt Instrument [Line Items]
Debt interest rate	5.125%
Subordinated Debt [Member] \| Subordinated Notes Payable at 5.125% Maturing June 1, 2015 [Member]
Debt Instrument [Line Items]
Debt interest rate	8.00%
Long-term Debt, Fiscal Year Maturity [Abstract]
Total long-term obligations	$ 15,000	15,000
Capital Lease Obligations [Member]
Long-term Debt, Fiscal Year Maturity [Abstract]
Total long-term obligations	5,701	9,226
Federal Home Loan Bank Advances [Member] \| Rates Ranging from 2.00% to 3.88% and Maturing Through September 2018 [Member]
Long-term Debt, Fiscal Year Maturity [Abstract]
Total long-term obligations	$ 660,237	510,252
Federal Home Loan Bank Advances [Member] \| Rates Ranging from 2.00% to 3.88% and Maturing Through September 2018 [Member] \| Minimum
Debt Instrument [Line Items]
Debt interest rate	2.00%
Federal Home Loan Bank Advances [Member] \| Rates Ranging from 2.00% to 3.88% and Maturing Through September 2018 [Member] \| Maximum
Debt Instrument [Line Items]
Debt interest rate	3.58%
Federal Home Loan Bank Advances [Member] \| Rates Ranging from 4.74% and Maturity of July 2017 [Member]
Debt Instrument [Line Items]
Debt interest rate	4.74%
Long-term Debt, Fiscal Year Maturity [Abstract]
Total long-term obligations	$ 0	10,000
Unamortized Purchase Accounting Adjustments [Member]
Long-term Debt, Fiscal Year Maturity [Abstract]
Total long-term obligations	(3,350)	(2,907)
Other Long Term Debt [Member]
Long-term Debt, Fiscal Year Maturity [Abstract]
Total long-term obligations	$ 30,095	$ 30,108
Libor 3 Month Rate [Member] \| Junior Subordinated Debt [Member] \| Junior Subordinanted Debenture at 3 Month Libor Plus 1.75% Maturing June 30, 2036 [Member]
Debt Instrument [Line Items]
Description of variable rate basis	3-month LIBOR
Basis spread on variable rate	1.75%
Libor 3 Month Rate [Member] \| Junior Subordinated Debt [Member] \| Junior Subordinated Debenture At 3 Month Libor Plus 2 Point 25 Percent Maturing June 15 2034 [Member] [Member]
Debt Instrument [Line Items]
Description of variable rate basis	3-month LIBOR
Basis spread on variable rate	2.25%
Libor 3 Month Rate [Member] \| Junior Subordinated Debt [Member] \| Junior Subordinated Debenture At 3 Month Libor Plus 2 Point 85 Percent Maturing April 7 2034 [Member] [Member]
Debt Instrument [Line Items]
Description of variable rate basis	3-month LIBOR
Basis spread on variable rate	2.85%

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