Fair Value Measurements - Balances and Levels of Assets Measured at Fair Value on Recurring and Nonrecurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Financial assets:
Available-for-sale securities, at fair value	$ 582,183	$ 649,387
Derivatives assets	19,745	6,023
Foreclosed real estate, net	7,403	11,641	$ 7,259	$ 8,796
Impaired loans	12,951	15,576
Financial liabilities:
Derivatives liabilities	586	369
Fair Value, Measurements, Recurring
Financial assets:
Available-for-sale securities, at fair value	582,183	649,387
Loans held for sale	507,442	273,196
Derivatives assets	19,745	6,023
Financial liabilities:
Derivatives liabilities	586	369
Fair Value, Measurements, Recurring | U.S. Government Agency Securities
Financial assets:
Available-for-sale securities, at fair value	985	33,808
Fair Value, Measurements, Recurring | Mortgage-backed Securities
Financial assets:
Available-for-sale securities, at fair value	443,908	522,373
Fair Value, Measurements, Recurring | Municipals, Tax Exempt
Financial assets:
Available-for-sale securities, at fair value	116,923	79,837
Fair Value, Measurements, Recurring | Treasury Securities
Financial assets:
Available-for-sale securities, at fair value	11,757	4,485
Fair Value, Measurements, Recurring | Equity Securities
Financial assets:
Available-for-sale securities, at fair value	8,610	8,884
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Financial assets:
Available-for-sale securities, at fair value	577,634	644,531
Loans held for sale	507,442	273,196
Derivatives assets	19,745	6,023
Financial liabilities:
Derivatives liabilities	586	369
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | U.S. Government Agency Securities
Financial assets:
Available-for-sale securities, at fair value	985	33,808
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Mortgage-backed Securities
Financial assets:
Available-for-sale securities, at fair value	443,908	522,373
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Municipals, Tax Exempt
Financial assets:
Available-for-sale securities, at fair value	116,923	79,837
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Treasury Securities
Financial assets:
Available-for-sale securities, at fair value	11,757	4,485
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Equity Securities
Financial assets:
Available-for-sale securities, at fair value	4,061	4,028
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)
Financial assets:
Available-for-sale securities, at fair value	4,549	4,856
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Equity Securities
Financial assets:
Available-for-sale securities, at fair value	4,549	4,856
Fair Value, Measurements, Nonrecurring
Financial assets:
Foreclosed real estate, net	2,315	6,275
Mortgage servicing rights, net	32,070	29,711
Impaired loans	1,281	29,135
Fair Value, Measurements, Nonrecurring | Commercial and Industrial
Financial assets:
Impaired loans	542	2,007
Fair Value, Measurements, Nonrecurring | Consumer and Other
Financial assets:
Impaired loans	1	4
Fair Value, Measurements, Nonrecurring | Owner Occupied | Commercial Real Estate
Financial assets:
Impaired loans	635	6,493
Fair Value, Measurements, Nonrecurring | Non-Owner Occupied | Commercial Real Estate
Financial assets:
Impaired loans		7,572
Fair Value, Measurements, Nonrecurring | 1-to-4 Family Mortgage | Residential Real Estate
Financial assets:
Impaired loans	103	6,127
Fair Value, Measurements, Nonrecurring | Construction Loans | Commercial Real Estate
Financial assets:
Impaired loans		6,896
Fair Value, Measurements, Nonrecurring | Multi-Family Mortgage | Residential Real Estate
Financial assets:
Impaired loans		36
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3)
Financial assets:
Foreclosed real estate, net	2,315	6,275
Mortgage servicing rights, net	32,070	29,711
Impaired loans	1,281	29,135
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3) | Commercial and Industrial
Financial assets:
Impaired loans	542	2,007
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3) | Consumer and Other
Financial assets:
Impaired loans	1	4
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3) | Owner Occupied | Commercial Real Estate
Financial assets:
Impaired loans	635	6,493
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3) | Non-Owner Occupied | Commercial Real Estate
Financial assets:
Impaired loans		7,572
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3) | 1-to-4 Family Mortgage | Residential Real Estate
Financial assets:
Impaired loans	$ 103	6,127
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3) | Construction Loans | Commercial Real Estate
Financial assets:
Impaired loans		6,896
Fair Value, Measurements, Nonrecurring | Significant Unobservable Inputs (Level 3) | Multi-Family Mortgage | Residential Real Estate
Financial assets:
Impaired loans		$ 36