Income Taxes (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
Income Taxes (Additional Textual) [Abstract]
One-time, non-cash tax charge		$ 700,000
Employee service share based compensation tax benefit realized from share based compensation plans	(700,000)	(2,300,000)	3,100,000
Additional income tax benefit related to discontinued operations	100,000	(2,900,000)	(500,000)
Estimated overall decrease in unrecognized tax benefits in the next twelve months due to the expiration of various statutes of limitations	13,300,000
Interest on income taxes accrued related to uncertain tax positions	2,100,000	1,900,000
Income tax penalties accrued related to uncertain tax positions	100,000	100,000
Unrealized tax benefits	14,141,000	18,952,000	16,123,000	12,417,000
Unrecognized tax benefits, affect effective tax rate if recognized	7,400,000
Tax positions for which ultimate deductibility is highly certain but timing is uncertain	6,700,000	10,000,000
Interest expense on uncertain tax positions	200,000	800,000	500,000
Penalty expense on uncertain tax positions	0	0	100,000
Federal [Member]
Income Taxes (Textual) [Abstract]
Net operating loss carryforwards	247,200,000
Deferred tax benefit operating loss carryforward	86,400,000
Credit carryforwards	4,100,000
Deferred tax benefit due to credit carryforwards expiration date	2029
Deferred tax benefit due to operating loss carry forwards expiration date	2030
Change in valuation allowance related to deferred tax assets	(300,000)
Federal [Member] | Charitable Contributions [Member]
Income Taxes (Textual) [Abstract]
Net operating loss carryforwards	3,600,000
Deferred tax benefit operating loss carryforward	1,200,000
Deferred tax benefit due to operating loss carry forwards expiration date	2013
State [Member]
Income Taxes (Textual) [Abstract]
Net operating loss carryforwards	628,600,000
Deferred tax benefit operating loss carryforward	26,600,000
Credit carryforwards	1,100,000
Deferred tax benefit due to credit carryforwards expiration date	2013
State net operating loss carryforwards expire date	between 2012 and 2031
Change in valuation allowance related to deferred tax assets	$ 1,500,000	$ 2,900,000	$ 1,900,000