Fair Value Measurements - Difference Between Fair Value and Carrying Amount of Residential Mortgage Loans Held for Sale (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Aggregate Fair Value	$ 26,234	$ 35,676
Difference	985	1,004
Contractual Principal	$ 25,249	$ 34,672

No definition available.

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- Definition

This item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of loans and long-term receivables (other than securities categorized as trading, available-for-sale or held-to-maturity) that have contractual principal amounts and for which the fair value option has been elected.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14064-108612

+ Details

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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

+ References

No definition available.

+ Details

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- Definition

Amount, after allowance for bad debt, of mortgage 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

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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