Accumulated Other Comprehensive Income (Loss) (Components Of Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands		3 Months Ended						9 Months Ended
		Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Other comprehensive income (loss), Pre-tax Amount		$ 1,907			$ (2,039)			$ 16,487	$ (13,243)
Other comprehensive income (loss), Tax Effect		481			(515)			4,157	(3,339)
Other comprehensive income (loss), before Reclassifications, Net-of-tax Amount		2,280			(1,808)			12,563	(10,570)
Amounts reclassified from accumulated other comprehensive income (loss)		(854)			284			(233)	666
Total other comprehensive income (loss), net of tax		1,426	$ 5,394	$ 5,510	(1,524)	$ (2,133)	$ (6,247)	12,330	(9,904)
Securities Available for Sale and Transferred Securities [Member]
Other comprehensive income (loss), before Reclassifications, Pre-tax Amount		2,992			(2,532)			17,222	(14,411)
Reclassification, Pre-tax Amount	[1]	(1,492)			209			(1,360)	381
Other comprehensive income (loss), Pre-tax Amount		1,500			(2,323)			15,862	(14,030)
Other comprehensive income (loss), before Reclassifications, Tax Effect		755			(639)			4,342	(3,633)
Reclassification, Tax Effect	[1]	(376)			52			(343)	96
Other comprehensive income (loss), Tax Effect		379			(587)			3,999	(3,537)
Other comprehensive income (loss), before Reclassifications, Net-of-tax Amount		2,237			(1,893)			12,880	(10,778)
Amounts reclassified from accumulated other comprehensive income (loss)	[1]	(1,116)			157			(1,017)	285
Total other comprehensive income (loss), net of tax		1,121			(1,736)			11,863	(10,493)
Accumulated Net Gain (Loss) from Cash Flow Hedges Including Portion Attributable to Noncontrolling Interest [Member]
Other comprehensive income (loss), Pre-tax Amount		57			114			(424)	278
Other comprehensive income (loss), Tax Effect		14			29			(107)	70
Total other comprehensive income (loss), net of tax		43			85			(317)	208
Accumulated Defined Benefit Plans Adjustment, Net Prior Service Including Portion Attributable to Noncontrolling Interest [Member]
Other comprehensive income (loss), Pre-tax Amount		(16)			(18)			(49)	(54)
Other comprehensive income (loss), Tax Effect		(4)			(4)			(12)	(14)
Total other comprehensive income (loss), net of tax		(12)			(14)			(37)	(40)
Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Including Portion Attributable to Noncontrolling Interest [Member]
Other comprehensive income (loss), Pre-tax Amount		366			188			1,098	563
Other comprehensive income (loss), Tax Effect		92			47			277	142
Total other comprehensive income (loss), net of tax		274			141			821	421
Accumulated Defined Benefit Plans Adjustment Including Portion Attributable to Noncontrolling Interest [Member]
Other comprehensive income (loss), Pre-tax Amount		350			170			1,049	509
Other comprehensive income (loss), Tax Effect		88			43			265	128
Total other comprehensive income (loss), net of tax		$ 262			$ 127			$ 784	$ 381

[1] Includes amounts related to the amortization/accretion of unrealized net gains and losses related to the Company’s reclassification of available for sale investment securities to the held to maturity category. The unrealized net gains/losses will be amortized/accreted over the remaining life of the investment securities as an adjustment of yield.