Loan Servicing (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Loan Servicing
Balance, beginning of period	$ 53,670	$ 55,553	$ 52,913
Paydowns	(5,504)	(4,230)	(5,177)
Changes in fair value due to changes in valuation inputs or assumptions used in the valuation model	2,950	(3,398)	(184)
Balance, end of period	66,079	53,670	55,553
Revenue from specified servicing fee	8,800	7,500	6,200
Escrow funds	502,700	378,500
Purchased servicing
Loan Servicing
Additions	1,209	1,357	1,135
Originated servicing
Loan Servicing
Additions	9,784	4,388	$ 6,866
RICHMAC
Loan Servicing
Additions	$ 3,970
Mortgage Loans
Loan Servicing
Sliding scale to deter prepayments (in years)	10 years
Unpaid principal balances of mortgage and other loans serviced for others	$ 5,000,000	4,000,000
Unpaid principal balances of loans sub‑serviced for others	$ 2,000,000	$ 1,400,000

The amount of revenue from servicing the loans retained, purchased and sun-serviced by the company.

No definition available.

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- Definition

The duration of sliding scale to deter prepayments.

+ References

No definition available.

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- Definition

Amount of unpaid principal balance of mortgage and other loans serviced for others.

+ References

No definition available.

+ Details

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- Definition

Amount of unpaid principal balance of loans sub‑serviced for others.

+ References

No definition available.

+ Details

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- Definition

The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

The value of new servicing assets, subsequently measured at fair value, acquired or created during the current period through purchases or from transfers of financial assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122625-111746

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- Definition

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122625-111746

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- Definition

Amount of increase (decrease) in fair value from changes in the inputs, assumptions, or model used to calculate the fair value of the contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)(4)(i)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122625-111746

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- Definition

Decrease in servicing assets subsequently measured at fair value resulting from conveyance of servicing rights to unrelated parties.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122625-111746

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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.

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