Summary of Significant Accounting Policies - Narrative (Details) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Materials Inventory
Inventory raw materials noncurrent	$ 3,000,000	$ 3,400,000
Accounts Receivable and Allowance for Doubtful Accounts
Allowance for doubtful accounts	$ 0	$ 0

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.4)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524

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