Significant Accounting Policies (Details Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012 Entity Category	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Accounting Policies [Abstract]
Overstatement in each of cash and cash equivalent, accounts payable and accrued expenses and in net cash provided by operating activities				$ 13.1
Wholly-owned bankruptcy remote special-purpose corporations	6
Number of categories for reservable assets	2
Gain (losses) from foreign currency transactions and from re-measurement of non-functional currency denominated assets and liabilities	0.5	(1.6)	(1.7)
Interest expense net of interest income on bank deposits	1.9	0.7	0.2
Total operating lease expense	$ 133.3	$ 137.3	$ 145.4