Summary of Accounting policies - Additional Information (Details) - USD ($)	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Accounting Policies [Abstract]
Stock Issued During Period, Shares, New Issues	960,488.00
Stock Issued During Period, Value, Other	$ 62.26
Proceeds from Issuance of Common Stock	57,306,000	$ 0
Debt issuance costs	$ (301,000)		$ (333,000)
Deferred Tax Assets, Net of Valuation Allowance, Current			$ 831,000