Stock Options, Employee Stock Purchase Plan and Restricted Stock (Details) - Non-vested Restricted Stock Activity - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Weighted Average Per Share Grant Date Fair Value
Canceled (in dollars per share)		$ 0.00
Restricted Stock [Member]
Number of Shares
Beginning balance, non-vested (in shares)	253	337	16
Granted (in shares)	302	0	337
Vested (in shares)	(118)	(84)	(16)
Canceled (in shares)	(21)	0	0
Ending balance, non-vested (in shares)	416	253	337
Weighted Average Per Share Grant Date Fair Value
Beginning balance, non-vested (in dollars per share)	$ 35.31	$ 35.31	$ 15.36
Granted (in dollars per share)	29.50	0.00	35.31
Vested (in dollars per share)	34.95	35.31	15.36
Canceled (in dollars per share)	28.85		0.00
Ending balance, non-vested (in dollars per share)	$ 31.52	$ 35.31	$ 35.31