Fair Value Measurements - (Details 7) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Financial assets
Securities held to maturity	$ 448,376	$ 458,400
Securities available for sale	653,444	646,805
Mortgage loans held for sale	298,365	225,254
Loans covered under loss-share agreements	44,989	93,142
FDIC loss-share indemnification asset	6,118	7,149
Mortgage servicing rights	13,366	29,642
Level 1
Financial assets
Cash and cash equivalents	218,483	211,571
Securities held to maturity	0	0
Securities available for sale	0	0
Mortgage loans held for sale	0	0
Loans covered under loss-share agreements	0	0
Loans not covered under loss-share agreements, net	0	0
FDIC loss-share indemnification asset	0	0
Mortgage servicing rights	0	0
Derivative instruments	0	0
Financial liabilities
Deposits	4,934,645	4,723,312
Short-term borrowings	414,255	422,279
Other long-term borrowings	181	192
Federal Home Loan Bank advances	0	0
Junior subordinated debentures	0	0
Derivative instruments	0	0
Level 2
Financial assets
Cash and cash equivalents	0	0
Securities held to maturity	448,376	473,753
Securities available for sale	634,497	627,336
Mortgage loans held for sale	298,365	225,254
Loans covered under loss-share agreements	0	0
Loans not covered under loss-share agreements, net	0	0
FDIC loss-share indemnification asset	0	0
Mortgage servicing rights	0	0
Derivative instruments	10,448	7,498
Financial liabilities
Deposits	1,504,606	1,502,202
Short-term borrowings	0	0
Other long-term borrowings	0	0
Federal Home Loan Bank advances	55,407	56,101
Junior subordinated debentures	75,218	78,095
Derivative instruments	14,392	7,319
Level 3
Financial assets
Cash and cash equivalents	0	0
Securities held to maturity	0	0
Securities available for sale	18,947	19,469
Mortgage loans held for sale	0	0
Loans covered under loss-share agreements	43,011	92,528
Loans not covered under loss-share agreements, net	5,456,034	5,208,630
FDIC loss-share indemnification asset	6,118	7,149
Mortgage servicing rights	13,615	33,283
Derivative instruments	0	0
Financial liabilities
Deposits	0	0
Short-term borrowings	0	0
Other long-term borrowings	0	0
Federal Home Loan Bank advances	0	0
Junior subordinated debentures	0	0
Derivative instruments	0	0
Carrying Value
Financial assets
Cash and cash equivalents	218,483	211,571
Securities held to maturity	448,376	458,400
Securities available for sale	653,444	646,805
Mortgage loans held for sale	298,365	225,254
Loans covered under loss-share agreements	44,989	93,142
Loans not covered under loss-share agreements, net	5,484,882	5,277,883
FDIC loss-share indemnification asset	6,118	7,149
Mortgage servicing rights	13,366	29,642
Derivative instruments	10,448	7,498
Financial liabilities
Deposits	6,431,377	6,218,602
Short-term borrowings	414,255	422,279
Other long-term borrowings	181	192
Federal Home Loan Bank advances	52,003	52,930
Junior subordinated debentures	95,232	95,095
Derivative instruments	14,392	7,319
Fair Value
Financial assets
Cash and cash equivalents	218,483	211,571
Securities held to maturity	448,376	473,753
Securities available for sale	653,444	646,805
Mortgage loans held for sale	298,365	225,254
Loans covered under loss-share agreements	43,011	92,528
Loans not covered under loss-share agreements, net	5,456,034	5,208,630
FDIC loss-share indemnification asset	6,118	7,149
Mortgage servicing rights	13,615	33,283
Derivative instruments	10,448	7,498
Financial liabilities
Deposits	6,439,251	6,225,514
Short-term borrowings	414,255	422,279
Other long-term borrowings	181	192
Federal Home Loan Bank advances	55,407	56,101
Junior subordinated debentures	75,218	78,095
Derivative instruments	$ 14,392	$ 7,319