Stockholders' Equity Stock-Based Compensation Expense (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Stock-based compensation expense
Stock-based compensation expense	$ 1,200,000	$ 855,000	$ 2,462,000	$ 1,577,000
Total unrecognized compensation costs related to non-vested stock options	12,100,000		$ 12,100,000
Remaining weighted-average period that unrecognized compensation costs are expected to be recognized			2 years 9 months 18 days
T2 Owned Instruments in Service
Stock-based compensation expense
Stock-based compensation expense	37,000		$ 65,000
Cost of product revenue
Stock-based compensation expense
Stock-based compensation expense	33,000		59,000
Research and development
Stock-based compensation expense
Stock-based compensation expense	341,000	297,000	610,000	577,000
Selling, general and administrative
Stock-based compensation expense
Stock-based compensation expense	$ 826,000	$ 558,000	$ 1,793,000	$ 1,000,000