Loans and Allowance for Credit Losses - Schedule of balance in the ACL and the recorded investment in loans (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Jun. 30, 2020
Beginning balance of allowance for loan losses	$ 35,084	$ 20,710	$ 25,139	$ 19,903	$ 19,903
Impact of CECL adoption			9,333
Provision charged to expense	612	388	1,385	1,284
Losses charged off	(246)	(310)	(416)	(416)
Recoveries	21	26	30	43
Ending balance of allowance for loan losses	35,471	20,814	35,471	20,814	25,139
Ending Balance: individually evaluated for impairment	232		232
Ending Balance: collectively evaluated for impairment	35,239	20,814	35,239	20,814	25,139
Ending Balance: loans acquired with deteriorated credit quality					0
Ending Balance: individually evaluated for impairment	904		904		0
Ending Balance: collectively evaluated for impairment	2,142,867		2,142,867		2,149,664
Ending Balance: loans acquired with deteriorated credit quality			15,412		21,799
Prior to adoption of CECL
Beginning balance of allowance for loan losses			25,139
Ending balance of allowance for loan losses					25,139
Consumer Loan
Beginning balance of allowance for loan losses	2,305	1,074	1,182	1,046	1,046
Impact of CECL adoption			1,065
Provision charged to expense	(882)	(4)	(823)	92
Losses charged off	(67)	(26)	(72)	(97)
Recoveries	6	6	10	9
Ending balance of allowance for loan losses	1,362	1,050	1,362	1,050	1,182
Ending Balance: collectively evaluated for impairment	1,362	1,050	1,362	1,050	1,182
Ending Balance: loans acquired with deteriorated credit quality					0
Ending Balance: individually evaluated for impairment					0
Ending Balance: collectively evaluated for impairment	79,590		79,590		80,767
Ending Balance: loans acquired with deteriorated credit quality					0
Consumer Loan \| Prior to adoption of CECL
Beginning balance of allowance for loan losses			1,182
Ending balance of allowance for loan losses					1,182
Commercial Loan
Beginning balance of allowance for loan losses	6,208	4,736	4,940	4,387	4,387
Impact of CECL adoption			1,012
Provision charged to expense	(49)	(57)	348	327
Losses charged off	(89)	(112)	(234)	(147)
Recoveries	15	1	19	1
Ending balance of allowance for loan losses	6,085	4,568	6,085	4,568	4,940
Ending Balance: collectively evaluated for impairment	6,085	4,568	6,085	4,568	4,940
Ending Balance: loans acquired with deteriorated credit quality					0
Ending Balance: individually evaluated for impairment					0
Ending Balance: collectively evaluated for impairment	424,169		424,169		463,902
Ending Balance: loans acquired with deteriorated credit quality			3,176		4,546
Commercial Loan \| Prior to adoption of CECL
Beginning balance of allowance for loan losses			4,940
Ending balance of allowance for loan losses					4,940
Construction Real Estate
Beginning balance of allowance for loan losses	1,892	1,539	2,010	1,365	1,365
Impact of CECL adoption			(121)
Provision charged to expense	495	118	498	292
Losses charged off		0
Recoveries		0
Ending balance of allowance for loan losses	2,387	1,657	2,387	1,657	2,010
Ending Balance: collectively evaluated for impairment	2,387	1,657	2,387	1,657	2,010
Ending Balance: loans acquired with deteriorated credit quality					0
Ending Balance: individually evaluated for impairment					0
Ending Balance: collectively evaluated for impairment	112,037		112,037		106,194
Ending Balance: loans acquired with deteriorated credit quality			957		1,278
Construction Real Estate \| Prior to adoption of CECL
Beginning balance of allowance for loan losses			2,010
Ending balance of allowance for loan losses					2,010
Residential real estate loans
Beginning balance of allowance for loan losses	8,629	3,572	4,875	3,706	3,706
Impact of CECL adoption			3,521
Provision charged to expense	1,859	294	2,112	160
Losses charged off	(90)	(172)	(110)	(172)
Recoveries		18		18
Ending balance of allowance for loan losses	10,398	3,712	10,398	3,712	4,875
Ending Balance: individually evaluated for impairment	232		232
Ending Balance: collectively evaluated for impairment	10,166	3,712	10,166	3,712	4,875
Ending Balance: loans acquired with deteriorated credit quality					0
Ending Balance: individually evaluated for impairment	904		904		0
Ending Balance: collectively evaluated for impairment	635,760		635,760		626,085
Ending Balance: loans acquired with deteriorated credit quality			26		1,272
Residential real estate loans \| Prior to adoption of CECL
Beginning balance of allowance for loan losses			4,875
Ending balance of allowance for loan losses					4,875
Commercial Real Estate
Beginning balance of allowance for loan losses	16,050	9,789	12,132	9,399	9,399
Impact of CECL adoption			3,856
Provision charged to expense	(811)	37	(750)	413
Losses charged off		0
Recoveries		1	1	15
Ending balance of allowance for loan losses	15,239	9,827	15,239	9,827	12,132
Ending Balance: collectively evaluated for impairment	15,239	$ 9,827	15,239	$ 9,827	12,132
Ending Balance: loans acquired with deteriorated credit quality					0
Ending Balance: individually evaluated for impairment					0
Ending Balance: collectively evaluated for impairment	$ 891,311		891,311		872,716
Ending Balance: loans acquired with deteriorated credit quality			11,253		14,703
Commercial Real Estate \| Prior to adoption of CECL
Beginning balance of allowance for loan losses			$ 12,132
Ending balance of allowance for loan losses					$ 12,132

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Represents the monetary amount of Financing Receivables Acquired with Deteriorated Credit Quality, during the indicated time period.

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No definition available.

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Represents the monetary amount of Financing Receivables Allowance for Credit Losses Acquired with Deteriorated Credit Quality, during the indicated time period.

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No definition available.

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Represents the monetary amount of Impact of CECL adoption, during the indicated time period.

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Amount of increase in allowance for credit loss on accounts receivable, from recovery.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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