Fair Value Measurements (Qualitative Information About Level 3 Assets Measured at Fair Value on a Nonrecurring Basis) (Details) - USD ($) $ in Thousands		3 Months Ended	12 Months Ended
		Mar. 31, 2019	Dec. 31, 2018
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Collateral dependent impaired loans	[1]	$ 868	$ 523
Nonrecurring [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Collateral dependent impaired loans		0	883
Property acquired through foreclosure or repossession			2,142
Nonrecurring [Member] | Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Collateral dependent impaired loans		$ 0	883
Property acquired through foreclosure or repossession			$ 2,142
Nonrecurring [Member] | Minimum [Member] | Appraisals Of Collateral [Member] | Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Appraisal adjustments	[2]		0.00%
Nonrecurring [Member] | Minimum [Member] | Collateral Dependent Impaired Loans [Member] | Appraisals Of Collateral [Member] | Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Discount for costs to sell		0.00%	0.00%
Appraisal adjustments	[2]	100.00%
Nonrecurring [Member] | Minimum [Member] | Property Acquired Through Foreclosure Or Repossession [Member] | Appraisals Of Collateral [Member] | Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Discount for costs to sell		0.00%	13.00%
Appraisal adjustments	[2]	0.00%	12.00%
Nonrecurring [Member] | Maximum [Member] | Appraisals Of Collateral [Member] | Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Appraisal adjustments	[2]		100.00%
Nonrecurring [Member] | Maximum [Member] | Collateral Dependent Impaired Loans [Member] | Appraisals Of Collateral [Member] | Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Discount for costs to sell		0.00%	10.00%
Appraisal adjustments	[2]	100.00%
Nonrecurring [Member] | Maximum [Member] | Property Acquired Through Foreclosure Or Repossession [Member] | Appraisals Of Collateral [Member] | Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Discount for costs to sell		0.00%	13.00%
Appraisal adjustments	[2]	0.00%	28.00%
Nonrecurring [Member] | Weighted Average [Member] | Appraisals Of Collateral [Member] | Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Appraisal adjustments	[2]		2.00%
Nonrecurring [Member] | Weighted Average [Member] | Collateral Dependent Impaired Loans [Member] | Appraisals Of Collateral [Member] | Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Discount for costs to sell		0.00%	10.00%
Appraisal adjustments	[2]	100.00%
Nonrecurring [Member] | Weighted Average [Member] | Property Acquired Through Foreclosure Or Repossession [Member] | Appraisals Of Collateral [Member] | Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Discount for costs to sell		0.00%	13.00%
Appraisal adjustments	[2]	0.00%	20.00%

[1] The recorded investment in impaired loans consists of unpaid principal balance, net of charge-offs, interest payments received applied to principal and unamortized deferred loan origination fees and costs. For accruing impaired loans (troubled debt restructurings for which management has concluded that the collectibility of the loan is not in doubt), the recorded investment also includes accrued interest.

[2] Management may adjust appraisal values to reflect market value declines or other discounts resulting from its knowledge of the property.