Equity Method Investment - Carrying value and Summarized financial information for Kleo (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended		9 Months Ended
	Jun. 30, 2017	Mar. 31, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Dec. 31, 2016
Equity Method Investment
Carrying value of investment in Kleo			$ 4,900		$ 2,753		$ 4,900	$ 2,753
Carrying value of equity method investment
Beginning balance					2,753
Purchases of Kleo common stock					2,999	$ 3,000
Loss recognized in connection with equity method investment			(638)	$ (75)	(1,204)	$ (75)
Ending balance			4,900		4,900
Kleo
Equity Method Investment
Carrying value of investment in Kleo			4,900		2,753		4,900	2,753
Carrying value of equity method investment
Beginning balance					2,753
Purchases of Kleo common stock	$ 1,375	$ 1,375			3,351
Loss recognized in connection with equity method investment			(638)		(1,204)
Ending balance			4,900		4,900
Assets
Current assets							5,977	4,276
Total assets							6,357	4,323
Liabilities
Current liabilities							536	413
Total liabilities							$ 4,225	$ 1,554
Profit/loss
Loss from operations			(1,784)		(4,305)
Net loss			$ (1,785)		$ (4,327)