Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) (Parenthetical) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Statement [Abstract]
Other comprehensive (loss) tax expense	$ 0.0	$ 0.0	$ 0.0	$ 0.0

Other comprehensive income loss unrealized gain loss on securities and foreign currency translation adjustments arising during period tax.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration