Mortgage Banking Operations - Loans Held for Sale (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Mortgage Loans on Real Estate [Line Items]
Loans held for sale	$ 851,126	$ 714,559
Single Family [Member]
Mortgage Loans on Real Estate [Line Items]
Single family, held-for-sale	730,042	656,334
Multifamily DUS [Member]
Mortgage Loans on Real Estate [Line Items]
Loans held for sale	47,014	35,506
Commercial Mortgage, excluding DUS [Member]
Mortgage Loans on Real Estate [Line Items]
Loans held for sale	$ 74,070	$ 22,719

The face amount of loans that will be sold to other entities.

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=65884687&loc=d3e4428-111522

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Amount, after allowance for bad debt, of loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

+ References

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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

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