Fair Value Measurements (Schedule Of Valuation Methodology And Unobservable Inputs) (Detail) - Significant Unobservable Inputs (Level 3) [Member] - Fair Value, Measurements, Nonrecurring [Member] $ in Thousands	9 Months Ended
	Sep. 30, 2017 USD ($)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
OREO	$ 2,587
Impaired Loans and Leases [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Collateral dependent impaired loans and leases	$ 15,955
Impaired Loans and Leases [Member] | Market Approach Valuation Technique [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	0.00%
Impaired Loans and Leases [Member] | Market Approach Valuation Technique [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	20.00%
Impaired Loans and Leases [Member] | Market Approach Valuation Technique - Discount for cost to sell [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	0.00%
Impaired Loans and Leases [Member] | Market Approach Valuation Technique - Discount for cost to sell [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	15.00%
Other Real Estate Owned [Member] | Market Approach Valuation Technique [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	0.00%
Other Real Estate Owned [Member] | Market Approach Valuation Technique [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	20.00%
Other Real Estate Owned [Member] | Market Approach Valuation Technique - Discount for cost to sell [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate (as a percent)	8.00%