Fair Value - Estimated Fair Value of Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Financial Assets:
Securities - held to maturity	$ 138,232	$ 140,315
FHLB and other stock	48,456	50,498
Financial Liabilities:
Time deposits	640,102	748,250
Fed funds purchased and securities sold under agreements to repurchase	52,875	75,177
Other borrowings	988,515	1,071,742
Trust preferred debentures	16,820	16,691
Level 1
Financial Assets:
Cash and cash equivalents	113,162	84,303
Securities - held to maturity	0	0
FHLB and other stock	0	0
Interest Receivable	0	0
Loans/leases, net	0	0
Financial Liabilities:
Time deposits	0	0
Other deposits	0	0
Fed funds purchased and securities sold under agreements to repurchase	0	0
Other borrowings	0	0
Trust preferred debentures	0	0
Accrued interest payable	0	0
Level 2
Financial Assets:
Cash and cash equivalents	0	0
Securities - held to maturity	138,232	140,315
FHLB and other stock	48,456	50,498
Interest Receivable	23,110	20,122
Loans/leases, net		4,617
Financial Liabilities:
Time deposits	633,148	744,310
Other deposits	4,384,980	4,089,557
Fed funds purchased and securities sold under agreements to repurchase	52,875	75,177
Other borrowings	1,005,170	1,069,609
Trust preferred debentures	21,697	22,012
Accrued interest payable	2,165	2,054
Level 3
Financial Assets:
Cash and cash equivalents	0	0
Securities - held to maturity	0	0
FHLB and other stock	0	0
Interest Receivable	0	0
Loans/leases, net	4,619,165	4,551,103
Financial Liabilities:
Time deposits	0	0
Other deposits	0	0
Fed funds purchased and securities sold under agreements to repurchase	0	0
Other borrowings	0	0
Trust preferred debentures	0	0
Accrued interest payable	0	0
Carrying Amount
Financial Assets:
Cash and cash equivalents	113,162	84,303
Securities - held to maturity	141,236	139,216
FHLB and other stock	48,456	50,498
Interest Receivable	23,110	20,122
Loans/leases, net	4,761,351	4,632,288
Financial Liabilities:
Time deposits	640,102	748,250
Other deposits	4,384,980	4,089,557
Fed funds purchased and securities sold under agreements to repurchase	52,875	75,177
Other borrowings	988,515	1,071,742
Trust preferred debentures	16,820	16,691
Accrued interest payable	2,165	2,054
Fair Value
Financial Assets:
Cash and cash equivalents	113,162	84,303
Securities - held to maturity	138,232	140,315
FHLB and other stock	48,456	50,498
Interest Receivable	23,110	20,122
Loans/leases, net	4,622,948	4,555,720
Financial Liabilities:
Time deposits	633,148	744,310
Other deposits	4,384,980	4,089,557
Fed funds purchased and securities sold under agreements to repurchase	52,875	75,177
Other borrowings	1,005,170	1,069,609
Trust preferred debentures	21,697	22,012
Accrued interest payable	$ 2,165	$ 2,054