Commitments and Contingencies (Narratives) (Details) - USD ($)	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Commitments And Contingencies Disclosure [Abstract]
Lease expiration date	Mar. 31, 2019
Rent expenses	$ 300,000	$ 300,000
Losses for contingent liability	0
Provision for a loss contingency	$ 0

No definition available.

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- Definition

Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

No definition available.

+ Details

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- Definition

Date which lease or group of leases is set to expire, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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- Definition

Amount of loss contingency liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

+ Details

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- Definition

Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges.

+ References

+ Details

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