Investment Securities, Available-for-sale Securities, Maturities (Details) $ in Thousands	Jun. 30, 2017 USD ($)
Amortized Cost [Abstract]
Due in one year or less	$ 50,482
Due in one year through five years	111,183
Due after five years through ten years	10,060
Due after ten years	0
Amortized Cost	612,165
Fair Value [Abstract]
Due in one year or less	50,397
Due in one year through five years	109,607
Due after five years through ten years	10,066
Due after ten years	0
Fair Value	605,422
Mortgage-Backed Securities and Collateralized Mortgage Obligations-Residential [Member]
Amortized Cost [Abstract]
Securities, amortized cost	355,966
Fair Value [Abstract]
Securities, fair value	352,591
Small Business Administration-Guaranteed Participation Securities [Member]
Amortized Cost [Abstract]
Securities, amortized cost	74,514
Fair Value [Abstract]
Securities, fair value	72,858
Mortgage-Backed Securities and Collateralized Mortgage Obligations-Commercial [Member]
Amortized Cost [Abstract]
Securities, amortized cost	9,960
Fair Value [Abstract]
Securities, fair value	$ 9,903