Loans Receivable, Net - Troubled Debt Restructurings (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020 USD ($) Loan	Sep. 30, 2019 USD ($) Loan	Sep. 30, 2020 USD ($) Loan	Sep. 30, 2019 USD ($) Loan
TDRs that occurred during the period
Number of loans \| Loan	6	6	16	14
Pre-modification recorded balance	$ 7,482	$ 3,168	$ 14,945	$ 5,261
Post-modification recorded balance	$ 7,482	$ 3,168	$ 14,945	$ 5,247
TDRs that subsequently defaulted
Number of loans \| Loan	0	0	0	1
Recorded balance	$ 0	$ 0	$ 0	$ 305
Residential Real Estate
TDRs that occurred during the period
Number of loans \| Loan	0	0	1	1
Pre-modification recorded balance	$ 0	$ 0	$ 210	$ 117
Post-modification recorded balance	$ 0	$ 0	$ 210	$ 123
TDRs that subsequently defaulted
Number of loans \| Loan	0	0	0	0
Recorded balance	$ 0	$ 0	$ 0	$ 0
Commercial Real Estate
TDRs that occurred during the period
Number of loans \| Loan	5	4	10	5
Pre-modification recorded balance	$ 6,648	$ 3,067	$ 13,392	$ 4,102
Post-modification recorded balance	$ 6,648	$ 3,067	$ 13,392	$ 4,102
TDRs that subsequently defaulted
Number of loans \| Loan	0	0	0	0
Recorded balance	$ 0	$ 0	$ 0	$ 0
Other Commercial
TDRs that occurred during the period
Number of loans \| Loan	1	2	4	4
Pre-modification recorded balance	$ 834	$ 101	$ 1,304	$ 668
Post-modification recorded balance	$ 834	$ 101	$ 1,304	$ 668
TDRs that subsequently defaulted
Number of loans \| Loan	0	0	0	0
Recorded balance	$ 0	$ 0	$ 0	$ 0
Home Equity
TDRs that occurred during the period
Number of loans \| Loan	0	0	1	1
Pre-modification recorded balance	$ 0	$ 0	$ 39	$ 103
Post-modification recorded balance	$ 0	$ 0	$ 39	$ 103
TDRs that subsequently defaulted
Number of loans \| Loan	0	0	0	0
Recorded balance	$ 0	$ 0	$ 0	$ 0
Other Consumer
TDRs that occurred during the period
Number of loans \| Loan	0	0	0	3
Pre-modification recorded balance	$ 0	$ 0	$ 0	$ 271
Post-modification recorded balance	$ 0	$ 0	$ 0	$ 251
TDRs that subsequently defaulted
Number of loans \| Loan	0	0	0	1
Recorded balance	$ 0	$ 0	$ 0	$ 305

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=121611835&loc=SL6953676-111524

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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=121611835&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=121611835&loc=SL6953682-111524

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