Subsequent Events (Details) (USD $) In Millions	0 Months Ended		0 Months Ended		0 Months Ended
Mar. 01, 2011	Sep. 30, 2011	Oct. 11, 2011 New Senior Credit Facility [Member]	Oct. 11, 2011 New Senior Credit Facility [Member] Term Loan Facility [Member]	Oct. 11, 2011 New Senior Credit Facility [Member] Revolving Credit Facility [Member]	Oct. 11, 2011 New Senior Credit Facility [Member] Letters Of Credit [Member]	Oct. 11, 2011 Amended Receivables Credit Facility Agreement [Member]	Oct. 11, 2011 Old Senior Credit Facility [Member]	Oct. 11, 2011 Receivables Credit Facility Agreement [Member]
Term loan facility borrowing capacity				$ 150
Credit facility borrowing capacity		$ 150.0			$ 250.0	$ 50.0	$ 200.0		$ 150.0
Credit facility, expiration date	February 28, 2012		October 11, 2016				October 11, 2014	April 2013

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant