FAIR VALUE - Summary of carrying amounts and estimated fair values for financial instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Assets
Cash and cash equivalents	$ 155,989	$ 78,638	$ 73,357
Loans, net	1,520,294	990,132
Mortgage loans held for sale	161,843	48,312
Accrued interest receivable	6,618	3,048
Liabilities
Deposits	1,619,910	1,086,784
FHLB Topeka Borrowings - fixed rate	149,563	10,000
Subordinated notes - fixed-to-floating rate	24,291	6,560
Accrued interest payable	453	299
Carrying Amount
Assets
Cash and cash equivalents	155,989	78,638
Loans, net	1,520,294	990,132
Mortgage loans held for sale	161,843	48,312
Accrued interest receivable	6,618	3,048
Liabilities
Deposits	1,619,910	1,086,784
FHLB Topeka Borrowings - fixed rate	15,000	10,000
Federal Reserve Borrowings - fixed rate	134,563
Accrued interest payable	453	299
2016 Subordinated notes - fixed-to-floating rate \| Carrying Amount
Liabilities
Subordinated notes - fixed-to-floating rate	24,291	6,560
Level 1 \| Estimated Fair Value
Assets
Cash and cash equivalents	155,989	78,638
Level 2 \| Estimated Fair Value
Assets
Mortgage loans held for sale	161,843	48,312
Accrued interest receivable	6,618	3,048
Liabilities
Deposits	1,621,648	1,089,261
FHLB Topeka Borrowings - fixed rate	15,099	10,003
Federal Reserve Borrowings - fixed rate	134,563
Accrued interest payable	453	299
Level 3 \| Estimated Fair Value
Assets
Loans, net	1,512,699	974,142
Level 3 \| 2016 Subordinated notes - fixed-to-floating rate \| Estimated Fair Value
Liabilities
Subordinated notes - fixed-to-floating rate	$ 25,750	$ 6,004

The fair value of borrowings under federal reserve bank.

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- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount of accrued but unpaid interest on deposit liabilities.

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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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Amount of short term borrowing where a bank borrows, at the federal funds rate, from another bank.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Junior Subordinated Notes, which have a lower priority than senior instruments.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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Fair value portion of mortgage loans held-for-sale.

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