Stock-Based Compensation (Details 4) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013
Share-based Compensation [Abstract]
Options Outstanding, Expected to Vest, Shares	1,491,252
Options Outstanding, Expected to Vest, Weighted-Average Exercise Price	$ 20.65
Options Outstanding, Expected to Vest, Aggregate Intrinsic Value	$ 26,334
Options Outstanding, Expected to Vest, Weighted-Average Remaining Term	4 years 7 months 10 days
Options Outstanding, Exercisable, Shares	1,164,670
Options Outstanding, Exercisable, Weighted-Average Exercise Price	$ 19.83
Options Outstanding, Exercisable, Aggregate Intrinsic Value	$ 21,519
Options Outstanding, Exercisable, Weighted-Average Remaining Term	4 years 0 months 22 days