Loans Receivable and Allowance for Loan Losses - Interest Income on Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	$ 31,540	$ 22,292	$ 27,297	$ 21,313
Interest Income Recognized	299	290	668	590
Real estate loans \| One-to-four family
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	8,647	8,611	8,728	9,149
Interest Income Recognized	81	108	188	214
Real estate loans \| Multifamily and commercial
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	14,960	2,666	10,840	2,681
Interest Income Recognized	32	37	198	74
Real estate loans \| Construction
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	0	1,700	0	1,133
Interest Income Recognized	0	0	0	25
Commercial business loans
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	5,871	6,616	5,640	5,430
Interest Income Recognized	157	98	224	178
Consumer loans \| Home equity loans and advances
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	2,062	2,699	2,089	2,920
Interest Income Recognized	$ 29	$ 47	$ 58	$ 99

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5258-111524

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

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