Loans Receivable, Net - Recorded Investment in Residential and Consumer Loans Based on Payment Activity Excluding PCI Loans (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Financing Receivable, Recorded Investment [Line Items]
Non-performing	$ 18,251	$ 20,865
Total loans	5,410,493	3,974,402
Residential Real Estate
Financing Receivable, Recorded Investment [Line Items]
Non-performing	5,686	4,190
Total loans	1,880,287	1,748,590
Consumer
Financing Receivable, Recorded Investment [Line Items]
Non-performing	1,992	1,929
Total loans	372,174	282,368
Residential Real Estate \| Residential Real Estate
Financing Receivable, Recorded Investment [Line Items]
Performing	1,874,601	1,744,400
Non-performing	5,686	4,190
Total loans	1,880,287	1,748,590
Residential Real Estate \| Consumer
Financing Receivable, Recorded Investment [Line Items]
Performing	370,182	280,439
Non-performing	1,992	1,929
Total loans	$ 372,174	$ 282,368

Credit quality of loan receivables performing.

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

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

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

+ Details

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- Definition

Reflects the carrying amount of loans deemed to be questionable as to collection on which no interest is continuing to be recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524

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