Fair Value Measurements And Fair Values Of Financial Instruments (Narrative) (Details)	Mar. 31, 2018 USD ($)
Fair Value Measurements And Fair Values Of Financial Instruments [Abstract]
Liabilities, nonrecurring basis	$ 0
Assets, Level 1 to Level 2 Transfers	0
Liabilities, Level 1 to Level 2 Transfers	$ 0

Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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

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- References

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- Definition

Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

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- Definition

Aggregation of the liabilities reported on the balance sheet measured at fair value on a nonrecurring basis by the entity.

+ References

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