Loans - Credit Quality (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016
Loans by risk rating
Total Loans	$ 1,539,647	$ 1,478,809	$ 1,161,151
Multifamily
Loans by risk rating
Total Loans	99,110	96,502
Commercial
Loans by risk rating
Total Loans	256,760	228,113	127,709
Lease financing receivables
Loans by risk rating
Total Loans	70,138	55,451	42,013
Real estate - commercial
Loans by risk rating
Total Loans	706,103		600,942
Real estate - commercial | Owner occupied general purpose
Loans by risk rating
Total Loans	141,053	137,236
Real estate - commercial | Owner occupied special purpose
Loans by risk rating
Total Loans	170,552	178,140
Real estate - commercial | Non-owner occupied general purpose
Loans by risk rating
Total Loans	217,343	232,291
Real estate - commercial | Non-owner occupied special purpose
Loans by risk rating
Total Loans	116,218	119,065
Real estate - commercial | Retail properties
Loans by risk rating
Total Loans	45,925	54,653
Real estate - commercial | Farm
Loans by risk rating
Total Loans	15,012	14,862
Real estate - residential
Loans by risk rating
Total Loans	398,170		352,595
Real estate - residential | Investor
Loans by risk rating
Total Loans	59,897	56,097
Real estate - residential | Owner occupied
Loans by risk rating
Total Loans	123,821	123,626
Real estate - residential | Revolving and junior liens
Loans by risk rating
Total Loans	115,342	101,626
Consumer
Loans by risk rating
Total Loans	2,878	3,237	2,966
All other
Loans by risk rating
Total Loans	11,937	13,190	12,722
Pass
Loans by risk rating
Total Loans	1,486,585	1,430,321
Pass | Multifamily
Loans by risk rating
Total Loans	94,286	96,502
Pass | Commercial
Loans by risk rating
Total Loans	238,814	214,028
Pass | Lease financing receivables
Loans by risk rating
Total Loans	68,780	53,366
Pass | Real estate - commercial | Owner occupied general purpose
Loans by risk rating
Total Loans	136,655	135,503
Pass | Real estate - commercial | Owner occupied special purpose
Loans by risk rating
Total Loans	165,945	172,353
Pass | Real estate - commercial | Non-owner occupied general purpose
Loans by risk rating
Total Loans	215,604	229,448
Pass | Real estate - commercial | Non-owner occupied special purpose
Loans by risk rating
Total Loans	112,543	114,293
Pass | Real estate - commercial | Retail properties
Loans by risk rating
Total Loans	43,535	52,207
Pass | Real estate - commercial | Farm
Loans by risk rating
Total Loans	12,494	11,840
Pass | Real estate - residential | Investor
Loans by risk rating
Total Loans	59,054	55,001
Pass | Real estate - residential | Owner occupied
Loans by risk rating
Total Loans	118,320	115,831
Pass | Real estate - residential | Revolving and junior liens
Loans by risk rating
Total Loans	113,379	99,286
Pass | Consumer
Loans by risk rating
Total Loans	2,869	3,236
Pass | All other
Loans by risk rating
Total Loans	11,937	13,165
Special Mention
Loans by risk rating
Total Loans	30,577	22,004
Special Mention | Commercial
Loans by risk rating
Total Loans	17,691	11,558
Special Mention | Lease financing receivables
Loans by risk rating
Total Loans	898	976
Special Mention | Real estate - commercial | Owner occupied general purpose
Loans by risk rating
Total Loans	3,174	53
Special Mention | Real estate - commercial | Owner occupied special purpose
Loans by risk rating
Total Loans	4,241	5,402
Special Mention | Real estate - commercial | Non-owner occupied general purpose
Loans by risk rating
Total Loans	654	913
Special Mention | Real estate - commercial | Retail properties
Loans by risk rating
Total Loans	1,246	1,267
Special Mention | Real estate - commercial | Farm
Loans by risk rating
Total Loans	1,213	1,240
Special Mention | Real estate - residential | Owner occupied
Loans by risk rating
Total Loans	566	570
Special Mention | All other
Loans by risk rating
Total Loans		25
Substandard
Loans by risk rating
Total Loans	22,485	26,484
Substandard | Multifamily
Loans by risk rating
Total Loans	4,824
Substandard | Commercial
Loans by risk rating
Total Loans	255	2,527
Substandard | Lease financing receivables
Loans by risk rating
Total Loans	460	1,109
Substandard | Real estate - commercial | Owner occupied general purpose
Loans by risk rating
Total Loans	1,224	1,680
Substandard | Real estate - commercial | Owner occupied special purpose
Loans by risk rating
Total Loans	366	385
Substandard | Real estate - commercial | Non-owner occupied general purpose
Loans by risk rating
Total Loans	1,085	1,930
Substandard | Real estate - commercial | Non-owner occupied special purpose
Loans by risk rating
Total Loans	3,675	4,772
Substandard | Real estate - commercial | Retail properties
Loans by risk rating
Total Loans	1,144	1,179
Substandard | Real estate - commercial | Farm
Loans by risk rating
Total Loans	1,305	1,782
Substandard | Real estate - residential | Investor
Loans by risk rating
Total Loans	843	1,096
Substandard | Real estate - residential | Owner occupied
Loans by risk rating
Total Loans	4,935	7,225
Substandard | Real estate - residential | Revolving and junior liens
Loans by risk rating
Total Loans	1,963	2,340
Substandard | Consumer
Loans by risk rating
Total Loans	9	1
Construction Loans | Real estate - commercial
Loans by risk rating
Total Loans	93,661		$ 22,204
Construction Loans | Real estate - commercial | Homebuilder
Loans by risk rating
Total Loans	1,947	3,883
Construction Loans | Real estate - commercial | Land
Loans by risk rating
Total Loans	2,870	3,029
Construction Loans | Real estate - commercial | Commercial speculative
Loans by risk rating
Total Loans	31,336	22,728
Construction Loans | Real estate - commercial | All other
Loans by risk rating
Total Loans	57,508	35,080
Construction Loans | Pass | Real estate - commercial | Homebuilder
Loans by risk rating
Total Loans	1,947	3,883
Construction Loans | Pass | Real estate - commercial | Land
Loans by risk rating
Total Loans	2,870	3,029
Construction Loans | Pass | Real estate - commercial | Commercial speculative
Loans by risk rating
Total Loans	31,267	22,654
Construction Loans | Pass | Real estate - commercial | All other
Loans by risk rating
Total Loans	56,286	34,696
Construction Loans | Special Mention | Real estate - commercial | All other
Loans by risk rating
Total Loans	894
Construction Loans | Substandard | Real estate - commercial | Commercial speculative
Loans by risk rating
Total Loans	69	74
Construction Loans | Substandard | Real estate - commercial | All other
Loans by risk rating
Total Loans	$ 328	$ 384