CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Unaudited) (Parenthetical) $ in Millions	3 Months Ended
Mar. 31, 2018 USD ($)
Statement Of Stockholders Equity [Abstract]
Common and preferred stock and warrants offering costs	$ 2.6

Common and preferred stock and warrants offering costs.

No definition available.

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