Commitments, Contingencies And Legal Proceedings (Details) (USD $)	12 Months Ended			3 Months Ended			3 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Jun. 30, 2011 Operating and Administrative Expenses [Member]	Apr. 30, 2011 Unfavorable Regulatory Action [Member]	Dec. 31, 2009 Unfavorable Regulatory Action [Member]	Jun. 30, 2011 Unfavorable Regulatory Action [Member] Operating and Administrative Expenses [Member]
Loss Contingencies [Line Items]
Operating leases rent expense	$ 12,300,000	$ 13,000,000	$ 14,300,000
Operating leases sub-lease proceeds	200,000	700,000	400,000
Stop loss insurance for workers compensation claims per incident	250,000
Stop loss insurance health care benefit claims per incident	200,000
Accrual for estimated claims exposure	2,000,000	2,300,000
Accrual for workers’ compensation estimated claims exposure	4,000,000	3,100,000
Estimated possible loss contingency					2,500,000	12,300,000
Benefit related to settlement				$ 9,700,000			$ 9,700,000