Income Taxes (Details) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Jun. 30, 2009
Income Tax Contingency [Line Items]
Income (Loss) from Continuing Operations before Income Taxes, Domestic									$ 93,302,000	$ 74,097,000	$ 53,930,000
Equity Method Investment Ownership Percentage Acquired	21.10%				21.10%				21.10%	21.10%
Business Acquisition, Purchase Price Allocation, Goodwill, Expected Tax Deductible Amount												11,216,000
Deferred Tax Asset, Built-in Gain	(3,537,000)				(4,068,000)				(3,537,000)	(4,068,000)
Deferred Tax Asset, Depreciation	(1,103,000)				(772,000)				(1,103,000)	(772,000)
Deferred Tax Asset, Cost Basis	386,000				256,000				386,000	256,000
Deferred Tax Assets, Deferred Income	151,000				230,000				151,000	230,000
Deferred Tax Liabilities, Other	(267,000)				56,000				(267,000)	56,000
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Reserves	11,035,000				13,160,000				11,035,000	13,160,000
Deferred Tax Asset, Goodwill	3,524,000				3,239,000				3,524,000	3,239,000
Deferred Tax Asset, Excess Interest Expense	5,299,000				5,678,000				5,299,000	5,678,000
Deferred Tax Assets, Operating Loss Carryforwards	6,805,000				5,398,000				6,805,000	5,398,000
Deferred Tax Assets, Gross	22,293,000				23,177,000				22,293,000	23,177,000
Deferred Tax Assets, Valuation Allowance	(18,021,000)				(18,021,000)				(18,021,000)	(18,021,000)
Deferred Tax Assets, Net	4,272,000				5,156,000				4,272,000	5,156,000
Current Federal Tax Expense (Benefit)									(79,000)	(254,000)	(419,000)
Current State and Local Tax Expense (Benefit)									(15,000)	(48,000)	(79,000)
Deferred Federal Income Tax Expense (Benefit)									(801,000)	(744,000)	1,110,000
Deferred State and Local Income Tax Expense (Benefit)									(82,000)	(54,000)	268,000
Income Tax Expense (Benefit), Including Discontinued Operations									977,000	1,100,000	(880,000)
Net Income (Loss) Attributable to Parent	$ 27,570,000	$ 22,632,000	$ 21,303,000	$ 20,820,000	$ 14,215,000	$ 21,210,000	$ 21,207,000	$ 16,365,000	$ 92,325,000	$ 72,997,000	$ 54,810,000