Loans - Summary of Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Accounts Notes And Loans Receivable [Line Items]
Total loans	$ 3,655,262	$ 2,552,016
Deferred expenses, net	8,465	3,693
Loans, net of deferred fees	3,663,727	2,555,709
Residential Properties
Accounts Notes And Loans Receivable [Line Items]
Total loans	2,581,245	1,780,889
Commercial Real Estate
Accounts Notes And Loans Receivable [Line Items]
Total loans	696,748	476,959
Commercial and Industrial Loans
Accounts Notes And Loans Receivable [Line Items]
Total loans	310,779	237,941
Consumer Loans
Accounts Notes And Loans Receivable [Line Items]
Total loans	29,330	32,127
Land
Accounts Notes And Loans Receivable [Line Items]
Total loans	37,160	24,100
Real Estate Loans
Accounts Notes And Loans Receivable [Line Items]
Total loans	3,315,153	2,281,948
Real Estate Loans \| Residential Properties
Accounts Notes And Loans Receivable [Line Items]
Total loans	2,581,245	1,780,889
Real Estate Loans \| Commercial Real Estate
Accounts Notes And Loans Receivable [Line Items]
Total loans	696,748	476,959
Real Estate Loans \| Land
Accounts Notes And Loans Receivable [Line Items]
Total loans	37,160	24,100
Multifamily \| Real Estate Loans \| Residential Properties
Accounts Notes And Loans Receivable [Line Items]
Total loans	1,935,429	1,178,003
Single Family \| Real Estate Loans \| Residential Properties
Accounts Notes And Loans Receivable [Line Items]
Total loans	$ 645,816	$ 602,886

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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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