Accounts Receivable Securitization Program (Details Textual) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Dec. 31, 2011
Accounts Receivable Securitization Program (Textual) [Abstract]
Maximum purchase limit for receivable interests under Accounts Receivable Securitization Program	$ 125
Amount available for accounts receivable securitization program	92.0	92.0
Level of eligible assets available under accounts receivable securitization program	lower than $125 million
Amount outstanding under accounts receivable securitization program	$ 0	$ 0
Accounts receivable securitization program expiration date	2012-12