Summary of Significant Accounting Policies (Fair Value Assumptions) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Weighted average grant-date fair value of options (in dollars per share)	$ 3.01	$ 3.76	$ 0.91
Expected volatility (percent)			53.30%
Risk-free interest rate (percent)			1.60%
Expected life in years	5 years 11 months 5 days	6 years 3 months 15 days	6 years 3 months 15 days
Dividend yield (percent)	$ 0	$ 0	$ 0
Minimum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Expected volatility (percent)	42.50%	54.10%
Risk-free interest rate (percent)	1.70%	1.60%
Maximum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Expected volatility (percent)	44.00%	55.20%
Risk-free interest rate (percent)	1.90%	1.90%