Fair Value Of Financial Instruments (Narrative) (Details) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Fair Value Of Financial Instruments [Abstract]
Total liabilities measured at fair value	$ 0	$ 0

Fair value of financial and nonfinancial obligations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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