Investment Securities, Available-for-sale Securities, Maturities (Details) $ in Thousands	Mar. 31, 2016 USD ($)
Amortized Cost [Abstract]
Due in one year or less	$ 1,956
Due in one year through five years	66,087
Due after five years through ten years	452
Due after ten years	9
Amortized Cost	589,542
Fair Value [Abstract]
Due in one year or less	1,958
Due in one year through five years	66,122
Due after five years through ten years	455
Due after ten years	9
Fair Value	590,093
Mortgage-Backed Securities and Collateralized Mortgage Obligations-Residential [Member]
Amortized Cost [Abstract]
Securities, amortized cost	421,323
Fair Value [Abstract]
Securities, fair value	422,189
Small Business Administration-Guaranteed Participation Securities [Member]
Amortized Cost [Abstract]
Securities, amortized cost	89,362
Fair Value [Abstract]
Securities, fair value	89,053
Mortgage-Backed Securities and Collateralized Mortgage Obligations-Commercial [Member]
Amortized Cost [Abstract]
Securities, amortized cost	10,353
Fair Value [Abstract]
Securities, fair value	$ 10,307