FAIR VALUE OF FINANCIAL INSTRUMENTS - Recurring and Nonrecurring basis (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Assets
Available-for-sale Securities	$ 385,340	$ 246,339
U.S. Treasury securities
Assets
Available-for-sale Securities	25,936	75,901
Government sponsored entity debt securities
Assets
Available-for-sale Securities	19,843	7,688
State and municipal securities
Assets
Available-for-sale Securities	40,182	25,274
Corporate securities
Assets
Available-for-sale Securities	54,049	47,405
Equity securities
Assets
Available-for-sale Securities	2,780
Level 1
Assets
Available-for-sale Securities	25,936	75,901
Level 2
Assets
Available-for-sale Securities	354,664	162,957
Loans held for sale	41,689	70,565
Level 2 \| Interest rate lock commitments
Assets
Derivative Assets	7,396	6,253
Level 2 \| Forward commitments to sell mortgage-backed securities
Assets
Derivative Assets	91	125
Level 2 \| Interest rate swap contracts
Assets
Derivative Assets	126
Liabilities
Derivative liability	126
Level 3
Assets
Available-for-sale Securities	4,740	7,481
Recurring member
Assets
Loans held for sale	41,689	70,565
Total Assets	434,642	323,282
Assets measured at fair value on a non-recurring basis:
Other real estate owned	134
Recurring member \| Interest rate lock commitments
Assets
Derivative Assets	7,396	6,253
Recurring member \| Forward commitments to sell mortgage-backed securities
Assets
Derivative Assets	91	125
Recurring member \| Interest rate swap contracts
Assets
Derivative Assets	126
Liabilities
Derivative liability	126
Recurring member \| U.S. Treasury securities
Assets
Available-for-sale Securities	25,936	75,901
Recurring member \| Government sponsored entity debt securities
Assets
Available-for-sale Securities	19,843	7,688
Recurring member \| Agency mortgage-backed securities
Assets
Available-for-sale Securities	242,550	90,070
Recurring member \| Non-agency mortgage-backed securities
Assets
Available-for-sale Securities		1
Recurring member \| State and municipal securities
Assets
Available-for-sale Securities	40,182	25,274
Recurring member \| Corporate securities
Assets
Available-for-sale Securities	54,049	47,405
Recurring member \| Equity securities
Assets
Available-for-sale Securities	2,780
Recurring member \| Level 1
Assets
Total Assets	25,936	75,901
Recurring member \| Level 1 \| U.S. Treasury securities
Assets
Available-for-sale Securities	25,936	75,901
Recurring member \| Level 2
Assets
Loans held for sale	41,689	70,565
Total Assets	403,966	239,900
Assets measured at fair value on a non-recurring basis:
Other real estate owned	134
Recurring member \| Level 2 \| Interest rate lock commitments
Assets
Derivative Assets	7,396	6,253
Recurring member \| Level 2 \| Forward commitments to sell mortgage-backed securities
Assets
Derivative Assets	91	125
Recurring member \| Level 2 \| Interest rate swap contracts
Assets
Derivative Assets	126
Liabilities
Derivative liability	126
Recurring member \| Level 2 \| Government sponsored entity debt securities
Assets
Available-for-sale Securities	19,843	7,688
Recurring member \| Level 2 \| Agency mortgage-backed securities
Assets
Available-for-sale Securities	242,550	90,070
Recurring member \| Level 2 \| State and municipal securities
Assets
Available-for-sale Securities	40,182	25,274
Recurring member \| Level 2 \| Corporate securities
Assets
Available-for-sale Securities	49,309	39,925
Recurring member \| Level 2 \| Equity securities
Assets
Available-for-sale Securities	2,780
Recurring member \| Level 3
Assets
Total Assets	4,740	7,481
Recurring member \| Level 3 \| Non-agency mortgage-backed securities
Assets
Available-for-sale Securities		1
Recurring member \| Level 3 \| Corporate securities
Assets
Available-for-sale Securities	4,740	7,480
Non recurring member
Assets measured at fair value on a non-recurring basis:
Mortgage servicing rights	70,277
Impaired loans	6,153	10,202
Other real estate owned		165
Assets held for sale	1,748	1,550
Non recurring member \| Level 2
Assets measured at fair value on a non-recurring basis:
Impaired loans	1,210	6,635
Other real estate owned		165
Assets held for sale	1,748	1,550
Non recurring member \| Level 3
Assets measured at fair value on a non-recurring basis:
Mortgage servicing rights	70,277
Impaired loans	$ 4,943	$ 3,567

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