Loans Receivable, Net - Troubled Debt Restructurings (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021 Loan	Sep. 30, 2020 USD ($) Loan	Sep. 30, 2021 USD ($) Loan	Sep. 30, 2020 USD ($) Loan
TDRs that occurred during the period
Number of loans \| Loan	0	6	10	16
Pre-modification recorded balance		$ 7,482	$ 2,368	$ 14,945
Post-modification recorded balance		$ 7,482	$ 2,368	$ 14,945
TDRs that subsequently defaulted
Number of loans \| Loan		0	0	0
Recorded balance		$ 0	$ 0	$ 0
Residential real estate
TDRs that occurred during the period
Number of loans \| Loan		0	1	1
Pre-modification recorded balance		$ 0	$ 210	$ 210
Post-modification recorded balance		$ 0	$ 210	$ 210
TDRs that subsequently defaulted
Number of loans \| Loan		0	0	0
Recorded balance		$ 0	$ 0	$ 0
Commercial real estate
TDRs that occurred during the period
Number of loans \| Loan		5	5	10
Pre-modification recorded balance		$ 6,648	$ 1,473	$ 13,392
Post-modification recorded balance		$ 6,648	$ 1,473	$ 13,392
TDRs that subsequently defaulted
Number of loans \| Loan		0	0	0
Recorded balance		$ 0	$ 0	$ 0
Other commercial
TDRs that occurred during the period
Number of loans \| Loan		1	3	4
Pre-modification recorded balance		$ 834	$ 554	$ 1,304
Post-modification recorded balance		$ 834	$ 554	$ 1,304
TDRs that subsequently defaulted
Number of loans \| Loan		0	0	0
Recorded balance		$ 0	$ 0	$ 0
Home equity
TDRs that occurred during the period
Number of loans \| Loan		0	0	1
Pre-modification recorded balance		$ 0	$ 0	$ 39
Post-modification recorded balance		$ 0	$ 0	$ 39
TDRs that subsequently defaulted
Number of loans \| Loan		0	0	0
Recorded balance		$ 0	$ 0	$ 0
Other consumer
TDRs that occurred during the period
Number of loans \| Loan		0	1	0
Pre-modification recorded balance		$ 0	$ 131	$ 0
Post-modification recorded balance		$ 0	$ 131	$ 0
TDRs that subsequently defaulted
Number of loans \| Loan		0	0	0
Recorded balance		$ 0	$ 0	$ 0

Number of financing receivables that have been modified by troubled debt restructurings.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

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Amount, before troubled debt restructuring, of financing receivable to be modified.

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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