Fair Value Accounting and Measurement (Financial Assets Accounted For Fair Value On Nonrecurring Basis) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities	$ 13,425	$ 0	$ 13,425	$ 0	$ 0	$ 0	$ 0	$ 0
Fair Value, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral dependent loans, Fair Value	7,976	4,837	7,976	4,837
Equity Securities	13,425		13,425
Fair Value, Inputs, Level 1 [Member] | Fair Value, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral dependent loans, Fair Value	0	0	0	0
Equity Securities	0		0
Fair Value, Inputs, Level 2 [Member] | Fair Value, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral dependent loans, Fair Value	0	0	0	0
Equity Securities	0		0
Fair Value, Inputs, Level 3 [Member] | Fair Value, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral dependent loans, Fair Value	7,976	4,837	7,976	4,837
Equity Securities	13,425		13,425
Collateral dependent loans [Domain] | Fair Value, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Option, Changes in Fair Value, Gain (Loss)	(6,946)	$ (2,124)	(7,745)	$ (2,525)
Equity Securities [Member] | Fair Value, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Option, Changes in Fair Value, Gain (Loss)	$ 13,425		$ 13,425