Notes Payable (Interest Expense) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Interest expense
Interest expense	$ 4,100,000	$ 2,000,000	$ 741,000
Non-cash interest	564,000	$ 354,000	$ 112,000
Extinguishment of debt	$ 112,000