Summary of Significant Accounting Policies - Recently Issued Accounting Pronouncements (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net cash provided by (used in) operating activities	$ (4,272)	$ (4,359)
ASU No. 2016-18 \| Reclassification Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net cash provided by (used in) operating activities		$ 770

Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3536-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3521-108585

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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