Significant Accounting Policies Significant Accounting Policies - Income Taxes (Details) (USD $)	Mar. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
Unrecognized Tax Benefits	$ 10,600,000	$ 10,600,000
Unrecognized Tax Benefits State Refund Claims	8,400,000	8,400,000
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	7,200,000	7,200,000
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit	8,600,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	$ 60,000	$ 56,000