Fair Value Measurements (Schedule Of Valuation Methodology And Unobservable Inputs) (Detail) - Fair Value, Measurements, Nonrecurring [Member] - Fair Value, Inputs, Level 3 [Member] $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($)
Nonperforming Financial Instruments [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Collateral dependent impaired loans and leases	$ 12,556
Nonperforming Financial Instruments [Member] \| Minimum [Member] \| Market Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rates	0.00%
Nonperforming Financial Instruments [Member] \| Minimum [Member] \| Market Approach Valuation Technique - Discount for cost to sell [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rates	0.00%
Nonperforming Financial Instruments [Member] \| Maximum [Member] \| Market Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rates	15.00%
Nonperforming Financial Instruments [Member] \| Maximum [Member] \| Market Approach Valuation Technique - Discount for cost to sell [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rates	8.00%
Other Real Estate Owned [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Other Assets, Fair Value Disclosure	$ 1,077
Other Real Estate Owned [Member] \| Market Approach Valuation Technique - Discount for cost to sell [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rates	8.00%
Other Real Estate Owned [Member] \| Minimum [Member] \| Market Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rates	0.00%
Other Real Estate Owned [Member] \| Maximum [Member] \| Market Approach Valuation Technique [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rates	20.00%

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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

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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- Definition

Fair value portion of other assets.

+ References

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