Income Taxes (Details 2) (USD $)	3 Months Ended						12 Months Ended
	Sep. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013
Operating loss carryforwards
Jobs credit provisions relative to credits generated during 2012							$ (2,900,000)
Jobs credits generated during 2013	100,000	3,300,000	0	0	0	0	(3,400,000)
Deferred tax assets:
Accounts receivable			9,191,000				4,278,000
Property and equipment			922,000				849,000
Workers' compensation costs			12,043,000				12,035,000
Compensated absences			5,081,000				5,665,000
Share-based compensation			2,425,000				3,367,000
Other insurance reserves			11,835,000				5,577,000
Unfavorable lease adjustments			857,000				506,000
Other liabilities and reserves			2,174,000				3,975,000
Deferred state income tax net operating loss carryforwards			3,233,000				3,611,000
Deferred tax credits, foreign tax credit carryforwards and other			2,123,000				1,689,000
Total gross deferred tax assets			49,884,000				41,552,000
Less valuation allowance			3,659,000				4,478,000
Net deferred tax assets			46,225,000				37,074,000
Deferred tax liabilities:
Revenue adjustments			5,651,000
Property and equipment			5,971,000				2,799,000
Goodwill and other intangible assets			122,031,000				129,828,000
Other			1,236,000				720,000
Total deferred tax liabilities			134,889,000				133,347,000
Net deferred tax liability			(88,664,000)				(96,273,000)
Classified as follows:
Current deferred income tax assets			17,589,000				19,811,000
Noncurrent deferred income tax liability			(106,253,000)				(116,084,000)
Net deferred tax liability			(88,664,000)				(96,273,000)
State
Operating loss carryforwards
Net operating loss carryforwards							77,000,000
Foreign
Operating loss carryforwards
Tax credit carryforwards							$ 900,000