Consolidated Statements of Comprehensive Loss (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2018	Jan. 01, 2018
Cumulative effect of change in accounting principles	$ (4,059)
Accounting Standards Update 2016-01
Cumulative effect of change in accounting principles		$ 500

Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

No definition available.

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