Stock Based Compensation (Stock Based Compensation Expense) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Stock-based compensation expense
Stock-based compensation expense	$ 4,730,000	$ 4,053,000	$ 1,653,000
T2 Owned Instruments in Service
Stock-based compensation expense
Stock-based compensation expense	118,000	115,000
Cost of product revenue
Stock-based compensation expense
Stock-based compensation expense	123,000
Research and development
Stock-based compensation expense
Stock-based compensation expense	1,127,000	1,213,000	501,000
Selling, general and administrative
Stock-based compensation expense
Stock-based compensation expense	$ 3,480,000	$ 2,840,000	$ 1,152,000