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.

No definition available.

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Rate at which loans or a loan portfolio are expected to prepay principal balances, used as an input to measure fair value.

+ References

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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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Fair Value Measurement - Quantitative Information about Recurring Level 3 Fair Value Measurements (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Constant prepayment rate	8.90%	8.80%	9.80%
Discount rate	13.00%	14.00%	10.00%
Mortgage Servicing Rights [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Mortgages Servicing Rights, Fair Value	$ 6,687	$ 6,595	$ 7,618	$ 7,378
Minimum [Member] \| Mortgage Servicing Rights [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate	13.00%	14.00%
Minimum [Member] \| Mortgage Servicing Rights [Member] \| Discounted Cash Flow [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Constant prepayment rate	6.20%	6.90%
Maximum [Member] \| Mortgage Servicing Rights [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate	15.00%	16.00%
Maximum [Member] \| Mortgage Servicing Rights [Member] \| Discounted Cash Flow [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Constant prepayment rate	22.00%	16.60%
Weighted Average [Member] \| Mortgage Servicing Rights [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate	13.00%	14.00%
Weighted Average [Member] \| Mortgage Servicing Rights [Member] \| Discounted Cash Flow [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Constant prepayment rate	8.90%	8.80%