Subsequent Event (Details) - Nova Merger Sub, Inc [Member] - Subsequent Event [Member]	Jul. 31, 2017 $ / shares
Subsequent Event [Line Items]
Number of business days merger offer open	20 days
Right to receive common stock in cash (in dollars per share)	$ 8.25

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration