Goodwill and Intangible Assets - Narrative (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill impairment loss	$ 0	$ 0	$ (8,344,000)
Deferred tax assets, other		3,200,000
Accumulated impairment loss		8,300,000	8,343,000
Aggregate amortization expense	$ 7,500,000	$ 6,000,000	$ 3,500,000