Description of Business and Summary of Significant Accounting Policies Capitalized Contract Costs (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Deferred Contract Costs [Roll Forward]
Capitalized Contract Cost, Net, beginning of period	$ 2,238
Capitalized Contract Cost, Amortization	(232)
Capitalized Contract Costs, net additions	131
Capitalized Contract Cost, Net, end of period	$ 2,137

Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant