Loans - Summary of Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Accounts Notes And Loans Receivable [Line Items]
Total loans	$ 3,905,684	$ 3,655,262
Deferred expenses, net	9,286	8,465
Loans, net of deferred fees	3,914,970	3,663,727
Residential Properties
Accounts Notes And Loans Receivable [Line Items]
Total loans	2,799,370	2,581,245
Commercial Real Estate
Accounts Notes And Loans Receivable [Line Items]
Total loans	708,458	696,748
Commercial and Industrial Loans
Accounts Notes And Loans Receivable [Line Items]
Total loans	337,295	310,779
Consumer Loans
Accounts Notes And Loans Receivable [Line Items]
Total loans	29,361	29,330
Land
Accounts Notes And Loans Receivable [Line Items]
Total loans	31,200	37,160
Real Estate Loans
Accounts Notes And Loans Receivable [Line Items]
Total loans	3,539,028	3,315,153
Real Estate Loans \| Residential Properties
Accounts Notes And Loans Receivable [Line Items]
Total loans	2,799,370	2,581,245
Real Estate Loans \| Commercial Real Estate
Accounts Notes And Loans Receivable [Line Items]
Total loans	708,458	696,748
Real Estate Loans \| Land
Accounts Notes And Loans Receivable [Line Items]
Total loans	31,200	37,160
Multifamily \| Real Estate Loans \| Residential Properties
Accounts Notes And Loans Receivable [Line Items]
Total loans	2,124,719	1,935,429
Single Family \| Real Estate Loans \| Residential Properties
Accounts Notes And Loans Receivable [Line Items]
Total loans	$ 674,651	$ 645,816

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

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Amount before allowance and after 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524

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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6378536&loc=d3e10092-111533

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