Stock-Based Compensation (Schedule of Nonvested Restricted Stock Units Activity) (Details)	9 Months Ended
	Sep. 30, 2016 $ / shares shares
Number of shares
Non-vested at beginning of period (in shares) | shares	909,410
Granted (in shares) | shares	678,051
Vested (in shares) | shares	(333,688)
Canceled / forfeited (in shares) | shares	(42,317)
Non-vested at end of period (in shares) | shares	1,211,456
Weighted- average grant date fair value per share
Non-vested at beginning of period (in dollars per share) | $ / shares	$ 6.37
Granted (in dollars per share) | $ / shares	5.69
Vested (in dollars per share) | $ / shares	5.24
Canceled / forfeited (in dollars per share) | $ / shares	4.94
Non-vested at end of period (in dollars per share) | $ / shares	$ 6.35