Intangible Assets (Schedule of Amortization and Future Amortization Expense) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Amortization expense on intangible assets	$ 3,627	$ 5,515
Estimated amortization expense, remainder of 2013	10,929
Estimated amortization expense, 2014	12,422
Estimated amortization expense, 2015	10,614
Estimated amortization expense, 2016	9,152
Estimated amortization expense, 2017	$ 7,989