Subsequent Events (Details Textual) (USD $) In Millions, except Share data, unless otherwise specified	9 Months Ended
	Sep. 30, 2011	Oct. 20, 2011	Oct. 09, 2011	Oct. 17, 2011 Senior Exchangeable Notes Due Two Thousand Twenty Six [Member]	Sep. 30, 2011 Acquisition [Member]
Subsequent Events (Additional Textual) [Abstract]
Outstanding senior exchangeable notes	1.50%			1.50%
Subsequent Event [Line Items]
Total consideration for the acquisition					$ 2,608
Cash to be paid for the acquisition					552.0
Subsequent Events (Textual) [Abstract]
Shares received by stockholders pursuant to merger			0.945
Cash received without interest for each share			$ 7.00
Company acquisition share price		$ 26.76
Increased in maximum borrowing capacity amendment of credit facility	600
Term loan to pay cash portion of the merger consideration	$ 400
Date of redemption of notes	2011-12-15