Fair Value Of Financial Instruments (Narrative) (Details) - USD ($)	Mar. 31, 2020	Dec. 31, 2019
Fair Value Of Financial Instruments [Abstract]
Liabilities measured at fair value	$ 0	$ 0
Transfers between level 1, 2, or 3	$ 0

Fair value of financial and nonfinancial obligations.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant