Long-Term Obligations (Tables)

12 Months Ended

Dec. 31, 2012

Debt Disclosure [Abstract]

Schedule of Long-term Debt Instruments [Table Text Block]

		2012			2011
Senior term notes	Notes payable, maturing in 2016, secured by assets, variable interest rate (1.96% and 2.00% at 2012 and 2011, respectively)	592,422			573,984
Revolving credit	Revolving line of credit, maturing in 2016, secured by assets, variable interest rate	—			—
Secured seller notes	Notes payable, various maturities through 2013, secured by assets and stock of certain subsidiaries, various interest rates ranging from 9.0% to 10.0%	266			346
	Total debt obligations	592,688			574,330
	Capital lease obligations	37,955			44,523
		630,643			618,853
	Less — current portion	(39,002		)	(32,571		)
		$	591,641		$	586,282

Schedule of Maturities of Long-term Debt [Table Text Block]

	Debt Obligations		Capital Lease Obligations		Total
2013	$	35,774	$	3,228	$	39,002
2014	47,344		3,249		50,593
2015	51,289		3,407		54,696
2016	458,281		3,126		461,407
2017	—		3,413		3,413
Thereafter	—		21,532		21,532
Total	$	592,688	$	37,955	$	630,643

Summary of Leverage Ratio in effect from time to time

Level	Leverage Ratio	Applicable Margin for Eurodollar Rate Loans		Applicable Revolving Commitment Fee %
I	≥ 2.50:1.00	2.25	%	0.50	%
II	< 2.50:1.00 and ≥ 1.75:1.00	1.75	%	0.375	%
III	< 1.75:1.00 and ≥ 1.00:1.00	1.50	%	0.25	%
IV	< 1.00:1.00	1.25	%	0.20	%

Scheduled principal payments for senior term notes

	2013		2014		2015		2016		2017
Senior term notes	$	35,508	$	47,344	$	51,289	$	458,281	$	—

Summary of cash received or cash paid and unrealized gains or losses

	For Years Ended December 31,
	2012		2011		2010
Cash paid(1)	$	—	$	—	$	382