Federal and state income taxes (Tables)

12 Months Ended

Dec. 31, 2011

Income Tax Disclosure [Abstract]

Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]

The components of the income tax provision (benefit) are as follows:

	Years Ended December 31,
	2011			2010			2009
	(Amounts in thousands)
Current:
Federal	$	(14,093	)	$	2,340		$	(4,908	)
State	9,825			7,795			10,322
Total current	(4,268		)	10,135			5,414
Deferred:
Federal	23,428			1,640			(4,193		)
State	7,388			(849		)	(3,927		)
Total deferred	30,816			791			(8,120		)
Tax benefit applied to reduce goodwill	1,204			1,204			1,204
Total	$	27,752		$	12,130		$	(1,502	)

Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]

The reconciliation of income tax at the federal statutory rate to the actual effective income tax rate is as follows:

	Years Ended December 31,
	2011		2010		2009
Federal statutory rate	35.0	%	35.0	%	35.0	%
State income tax expense, net of federal benefit	40.1		19.7		(45.1	)
Change in uncertain tax provisions	0.4		0.2		32.2
Nondeductible expenses for tax purposes	6.8		6.8		(17.8	)
Tax credits	(2.0	)	(3.8	)	15.7
Other	—		0.5		4.3
	80.3	%	58.4	%	24.3	%

Schedule of Deferred Tax Assets and Liabilities [Table Text Block]

Significant components of the Company’s deferred income taxes consisted of the following:

	December 31,
	2011			2010
	(Amounts in thousands)
Deferred income tax assets:
Goodwill amortization	$	116,902		$	135,572
Net operating loss carryforwards	11,099			10,893
Deferred compensation	7,871			9,009
Accrued expenses	6,424			9,481
Stock-based compensation	16,444			13,961
Accrued vacation	2,109			2,242
Other	226			1,961
Total deferred income tax assets	161,075			183,119
Deferred income tax liabilities:
Property and equipment	(157,185		)	(148,335		)
Prepaid insurance	(1,489		)	(1,662		)
Other	(2,170		)	—
Total deferred income tax liabilities	(160,844		)	(149,997		)
Net deferred income tax assets	$	231		$	33,122