Fair Value Measurements (Recurring Basis) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	$ 1,234,964	$ 553,731
Loan servicing rights	48,085	0
U.S. Treasury securities
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	5,793	5,765
Government sponsored agencies
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	215,011	194,989
State and political subdivisions
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	300,088	15,120
Residential mortgage-backed securities
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	272,282	187,768
Collateralized mortgage obligations
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	320,025	132,230
Corporate bonds
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	89,474	14,627
Preferred stock and trust preferred securities
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	32,291	3,232
Recurring
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	1,234,964	553,731
Loans held-for-sale	81,830	10,327
Loan servicing rights	48,085
Derivative assets	8,215	2,018
Total assets measured at fair value on a recurring basis	1,373,094	566,076
Derivative liabilities	6,359	1,979
Total liabilities at fair value	6,359	1,979
Recurring | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	5,793	5,765
Loans held-for-sale	0	0
Loan servicing rights	0
Derivative assets	0	0
Total assets measured at fair value on a recurring basis	5,793	5,765
Derivative liabilities	0	0
Total liabilities at fair value	0	0
Recurring | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	1,229,171	547,966
Loans held-for-sale	81,830	10,327
Loan servicing rights	0
Derivative assets	8,215	2,018
Total assets measured at fair value on a recurring basis	1,319,216	560,311
Derivative liabilities	6,359	1,979
Total liabilities at fair value	6,359	1,979
Recurring | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Loans held-for-sale	0	0
Loan servicing rights	48,085
Derivative assets	0	0
Total assets measured at fair value on a recurring basis	48,085	0
Derivative liabilities	0	0
Total liabilities at fair value	0	0
Recurring | Customer-initiated derivatives
Summary of assets measured at fair value on a recurring basis
Derivative assets	4,406
Derivative liabilities	4,141
Recurring | Customer-initiated derivatives | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a recurring basis
Derivative assets	0
Derivative liabilities	0
Recurring | Customer-initiated derivatives | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a recurring basis
Derivative assets	4,406
Derivative liabilities	4,141
Recurring | Customer-initiated derivatives | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a recurring basis
Derivative assets	0
Derivative liabilities	0
Recurring | Forward contracts related to mortgage loans to be delivered for sale
Summary of assets measured at fair value on a recurring basis
Derivative assets	635	144
Derivative liabilities		57
Recurring | Forward contracts related to mortgage loans to be delivered for sale | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a recurring basis
Derivative assets	0	0
Derivative liabilities		0
Recurring | Forward contracts related to mortgage loans to be delivered for sale | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a recurring basis
Derivative assets	635	144
Derivative liabilities		57
Recurring | Forward contracts related to mortgage loans to be delivered for sale | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a recurring basis
Derivative assets	0	0
Derivative liabilities		0
Recurring | Interest rate lock commitments
Summary of assets measured at fair value on a recurring basis
Derivative assets	956	42
Derivative liabilities		90
Recurring | Interest rate lock commitments | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a recurring basis
Derivative assets	0	0
Derivative liabilities		0
Recurring | Interest rate lock commitments | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a recurring basis
Derivative assets	956	42
Derivative liabilities		90
Recurring | Interest rate lock commitments | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a recurring basis
Derivative assets	0	0
Derivative liabilities		0
Recurring | Power Equity CD
Summary of assets measured at fair value on a recurring basis
Derivative assets	2,218	1,832
Derivative liabilities	2,218	1,832
Recurring | Power Equity CD | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a recurring basis
Derivative assets	0	0
Derivative liabilities	0	0
Recurring | Power Equity CD | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a recurring basis
Derivative assets	2,218	1,832
Derivative liabilities	2,218	1,832
Recurring | Power Equity CD | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a recurring basis
Derivative assets	0	0
Derivative liabilities	0	0
Recurring | U.S. Treasury securities
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	5,793	5,765
Recurring | U.S. Treasury securities | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	5,793	5,765
Recurring | U.S. Treasury securities | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | U.S. Treasury securities | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | Government sponsored agencies
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	215,011	194,989
Recurring | Government sponsored agencies | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | Government sponsored agencies | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	215,011	194,989
Recurring | Government sponsored agencies | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | State and political subdivisions
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	300,088	15,120
Recurring | State and political subdivisions | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | State and political subdivisions | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	300,088	15,120
Recurring | State and political subdivisions | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | Residential mortgage-backed securities
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	272,282	187,768
Recurring | Residential mortgage-backed securities | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | Residential mortgage-backed securities | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	272,282	187,768
Recurring | Residential mortgage-backed securities | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | Collateralized mortgage obligations
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	320,025	132,230
Recurring | Collateralized mortgage obligations | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | Collateralized mortgage obligations | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	320,025	132,230
Recurring | Collateralized mortgage obligations | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | Corporate bonds
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	89,474	14,627
Recurring | Corporate bonds | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | Corporate bonds | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	89,474	14,627
Recurring | Corporate bonds | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | Preferred stock and trust preferred securities
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	32,291	3,232
Recurring | Preferred stock and trust preferred securities | Quoted Prices In Active Markets for Identical Assets (Level 1)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	0	0
Recurring | Preferred stock and trust preferred securities | Significant Other Observable Inputs (Level 2)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	32,291	3,232
Recurring | Preferred stock and trust preferred securities | Significant Unobservable Inputs (Level 3)
Summary of assets measured at fair value on a recurring basis
Available-for-sale, at fair value	$ 0	$ 0