FAIR VALUE MEASURES - Difference Between Fair Value and Principal Balance for Mortgage Loans Held for Sale Measured at Fair Value (Details) - Loans held for sale - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Aggregate fair value of mortgage loans held for sale	$ 190,445	$ 105,924
Aggregate unpaid principal balance	185,814	103,691
Past due loans of 90 days or more	0	0
Nonaccrual loans	$ 0	$ 0

Aggregate fair value of loans held for sale.

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- Definition

Aggregate Unpaid Principal Balance Of Items For Which Fair Value Option Was Elected

+ References

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.

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- Definition

For loans held as assets for which the fair value option has been elected, this item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of those loans that are 90 days or more past due.

+ 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 (e)(3)
-URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14064-108612

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- Definition

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