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FAIR VALUE OF FINANCIAL INSTRUMENTS - Recurring and Nonrecurring basis (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Assets
Investment securities available for sale	$ 656,254		$ 649,433
Equity securities recorded at fair value	5,640		5,621
Loans held for sale	113,852		16,431
Assets measured at fair value on a non-recurring basis:
Mortgage servicing rights held for sale	1,460		1,972
Losses recognized on assets measured on non-recurring basis
Loans servicing rights	8,468	$ 25
Loss on mortgage servicing rights held for sale	496
Impairment of assets held for sale	642
U.S. government sponsored entities and U.S. agency securities
Assets
Investment securities available for sale	47,357		60,020
Agency mortgage-backed securities
Assets
Investment securities available for sale	326,700		324,974
Non-agency mortgage-backed securities
Assets
Investment securities available for sale	27,281		17,148
State and municipal securities
Assets
Investment securities available for sale	116,094		124,555
Corporate Securities
Assets
Investment securities available for sale	138,822		122,736
Recurring member
Assets
Loans held for sale	113,852		16,431
Total Assets	780,939		675,141
Recurring member \| U.S. government sponsored entities and U.S. agency securities
Assets
Investment securities available for sale	47,357		60,020
Recurring member \| Agency mortgage-backed securities
Assets
Investment securities available for sale	326,700		324,974
Recurring member \| Non-agency mortgage-backed securities
Assets
Investment securities available for sale	27,281		17,148
Recurring member \| State and municipal securities
Assets
Investment securities available for sale	116,094		124,555
Recurring member \| Corporate Securities
Assets
Investment securities available for sale	138,822		122,736
Recurring member \| Corporate Securities
Assets
Equity securities recorded at fair value	5,640		5,621
Recurring member \| Interest rate lock commitments
Assets
Derivative Assets	4,305		3,350
Recurring member \| Interest rate swap contracts
Assets
Derivative Assets	888		306
Liabilities
Derivative liability	888		306
Recurring member \| Level 2
Assets
Loans held for sale	113,852		16,431
Total Assets	780,014		674,186
Recurring member \| Level 2 \| U.S. government sponsored entities and U.S. agency securities
Assets
Investment securities available for sale	47,357		60,020
Recurring member \| Level 2 \| Agency mortgage-backed securities
Assets
Investment securities available for sale	326,700		324,974
Recurring member \| Level 2 \| Non-agency mortgage-backed securities
Assets
Investment securities available for sale	27,281		17,148
Recurring member \| Level 2 \| State and municipal securities
Assets
Investment securities available for sale	116,094		124,555
Recurring member \| Level 2 \| Corporate Securities
Assets
Investment securities available for sale	137,897		121,781
Recurring member \| Level 2 \| Corporate Securities
Assets
Equity securities recorded at fair value	5,640		5,621
Recurring member \| Level 2 \| Interest rate lock commitments
Assets
Derivative Assets	4,305		3,350
Recurring member \| Level 2 \| Interest rate swap contracts
Assets
Derivative Assets	888		306
Liabilities
Derivative liability	888		306
Recurring member \| Level 3
Assets
Total Assets	925		955
Recurring member \| Level 3 \| Corporate Securities
Assets
Investment securities available for sale	925		955
Non recurring member
Assets measured at fair value on a non-recurring basis:
Loan servicing rights	44,566		53,824
Mortgage servicing rights held for sale	1,460		1,972
Nonperforming loans	15,972		14,693
Other real estate owned	909
Assets held for sale	3,790		3,974
Losses recognized on assets measured on non-recurring basis
Loans servicing rights	8,468	25
Loss on mortgage servicing rights held for sale	496
Nonperforming loans	12,919	981
Other real estate owned	605	16
Impairment of assets held for sale	146
Total loss on assets measured on a nonrecurring basis	22,634	$ 1,022
Non recurring member \| Level 2
Assets measured at fair value on a non-recurring basis:
Nonperforming loans	15,450		12,518
Other real estate owned	909
Assets held for sale	3,790		3,974
Non recurring member \| Level 3
Assets measured at fair value on a non-recurring basis:
Loan servicing rights	44,566		53,824
Mortgage servicing rights held for sale	1,460		1,972
Nonperforming loans	$ 522		$ 2,175