Description of the Business and Summary of Significant Accounting Policies (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2011 Venture segment	Dec. 31, 2010	Dec. 31, 2009
Description of the Business and Summary of Significant Accounting Policies (Textual) [Abstract]
Number of business segments	3
Number of joint ventures	2
Period of maturity for cash and cash equivalents	Three months or less
Period of original maturity for certificate of deposits	Greater than three months
Net cash refunds of income tax payments	$ 1,500,000	$ 65,400,000	$ 3,800,000
Cash payments of income taxes	1,300,000	1,300,000	1,600,000
Percent of trade receivables per customer maximum	10.00%
Write off of deferred debt issuance cost associated with senior notes		300,000	4,200,000
Write-off of deferred financing costs related to refinancing of credit facility	1,681,000
Effect of dilutive stock-based compensation awards		709,000
Amortization of deferred financing costs	5,118,000	5,314,000	4,762,000
Amortization expense of deferred software costs	8,700,000	8,200,000	7,100,000
Advertising costs included in continuing operations	22,200,000	25,600,000	18,700,000
Potentially issuable shares under the conversion spread		413,000	0
Initial strike price under warrant	$ 32.70
Approximate number of common stock share which can be purchased under warrants	13,200,000
Convertible Notes Payable [Member]
Debt Instrument [Line Items]
Interest	3.75%
Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Stock-based compensation awards outstanding	1,401,000	1,628,000	3,546,000
Software Development [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful life of deferred software costs, minimum	3
Estimated useful life of deferred software costs, maximum	5
Minimum [Member]
Schedule of Investments [Line Items]
Interest in non-marketable investments using equity method of accounting	20.00%
Maximum [Member]
Schedule of Investments [Line Items]
Maximum interest in non-marketable investments using cost method of accounting	20.00%
Interest in non-marketable investments using equity method of accounting	50.00%
Osceola County [Member]
Operating Leases of Lessee, County [Line Items]
Land area covered under operating lease agreement	65.3
Grapevine [Member]
Operating Leases of Lessee, County [Line Items]
Land area covered under operating lease agreement	10.0
Interest rate swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Deferred taxes, net	(159,000)	(2,408,000)
Amount of deferred tax on derivative instrument	4,526,000	7,222,000
Natural gas swaps [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Deferred taxes, net	(189,000)	(184,000)
Amount of deferred tax on derivative instrument	$ 270,000	$ 103,000