Share-based Compensation (Stock Option Activity) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Stock Options, Outstanding [Roll Forward]
Stock options outstanding, ending balance	792,000
Stock options, Exercisable	679,500
Stock Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Stock options, Weighted Average Exercise Price, beginning balance (in dollars per share)	$ 4.03	$ 2.51	$ 2.22
Stock options, Granted, Weighted Average Exercise Price (in dollars per share)	$ 14.89	$ 16.94	$ 20.58
Stock options, Exercised, Weighted Average Exercise Price (in dollars per share)	$ 1.73	$ 0.75	$ 0.73
Stock options, Canceled, Weighted Average Exercise Price (in dollars per share)	$ 0	$ 0.00	$ 0.72
Stock options, Weighted Average Exercise Price, ending balance (in dollars per share)	$ 8.28	$ 4.03	$ 2.51	$ 2.22
Stock options, Exercisable, Weighted Average Exercise Price (in dollars per share)	$ 6.78
Stock Options, Additional Disclosures [Abstract]
Stock options outstanding, Weighted Average Remaining Contractual Term (in years)	1 year	1 year 2 months 1 day	1 year 6 months 21 days	2 years 6 months 3 days
Stock options, Exercisable, Weighted Average Remaining Contractual Term (in years)	7 months 23 days
Stock options outstanding, Aggregate Intrinsic Value	$ 5,093	$ 24,171	$ 64,959	$ 71,638
Stock options, Exercisable, Aggregate Intrinsic Value	5,387
Proceeds from stock options exercised	2,161	1,020	51
Stock Options [Member]
Stock Options, Additional Disclosures [Abstract]
Stock options exercised in period, intrinsic value	$ 11,400	$ 24,800	$ 941
Within Plans [Member]
Stock Options, Outstanding [Roll Forward]
Stock options outstanding, beginning balance	1,998,633	3,315,175	3,340,476
Stock options, Granted	45,000	45,000	45,000
Stock options, Exercised	(1,251,633)	(1,361,542)	(69,509)
Stock options, Canceled	0	0	(792)
Stock options outstanding, ending balance	792,000	1,998,633	3,315,175
Stock options, Exercisable	679,500