Derivative Instruments (Change In Fair Value Of Derivative Instruments) (Details) - Not Designated as Hedging Instrument - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Derivative assets \| Other Income
Derivatives, Fair Value [Line Items]
Change in Fair Value	$ 27,240	$ 4,342	$ 1,316
Derivative liabilities \| Other Income
Derivatives, Fair Value [Line Items]
Change in Fair Value	(27,240)	(4,342)	(1,316)
Derivative liabilities \| Other Expense
Derivatives, Fair Value [Line Items]
Change in Fair Value	$ 206	$ 165	$ 50

Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=121577467&loc=d3e76258-113986

Name:	us-gaap_ChangeInUnrealizedGainLossOnFairValueHedgingInstruments1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration