Long-Term Debt (Details) In Millions, unless otherwise specified			0 Months Ended			0 Months Ended			9 Months Ended			9 Months Ended						9 Months Ended			1 Months Ended				1 Months Ended	9 Months Ended		9 Months Ended
	Sep. 30, 2014 USD ($)	Dec. 31, 2013 USD ($)	Apr. 02, 2014 US Credit Agreement Revolving Credit Line USD ($)	Sep. 30, 2014 US Credit Agreement Revolving Credit Line USD ($)	Dec. 31, 2013 US Credit Agreement Revolving Credit Line USD ($)	Apr. 02, 2014 US Credit Agreement Term Loan USD ($)	Sep. 30, 2014 US Credit Agreement Term Loan USD ($)	Dec. 31, 2013 US Credit Agreement Term Loan USD ($)	Sep. 30, 2014 UK Credit Agreement Revolving Credit Line USD ($)	Sep. 30, 2014 UK Credit Agreement Revolving Credit Line GBP (£)	Dec. 31, 2013 UK Credit Agreement Revolving Credit Line USD ($)	Sep. 30, 2014 UK Credit Agreement Revolving Credit Line Minimum	Sep. 30, 2014 UK Credit Agreement Revolving Credit Line Maximum	Sep. 30, 2014 U.K. Agreement Term Loan GBP (£)	Sep. 30, 2014 U.K. Agreement Term Loan USD ($)	Dec. 31, 2013 U.K. Agreement Term Loan USD ($)	Dec. 31, 2012 U.K. Agreement Term Loan GBP (£)	Sep. 30, 2014 U.K. Agreement Term Loan Minimum	Sep. 30, 2014 U.K. Agreement Term Loan Maximum	Sep. 30, 2014 UK Credit Agreement Overdraft Line of Credit GBP (£)	Aug. 31, 2012 5.75% senior subordinated notes due 2022 USD ($)	Sep. 30, 2014 5.75% senior subordinated notes due 2022 USD ($)	Dec. 31, 2013 5.75% senior subordinated notes due 2022 USD ($)	Dec. 31, 2012 5.75% senior subordinated notes due 2022	Aug. 31, 2012 5.75% senior subordinated notes due 2022 Maximum Debt redemption prior to October 1, 2015	Sep. 30, 2014 Rental car revolver USD ($)	Dec. 31, 2013 Rental car revolver USD ($)	Sep. 30, 2014 Working Capital Loan Agreement USD ($)	Dec. 31, 2013 Working Capital Loan Agreement USD ($)	Dec. 31, 2013 Working Capital Loan Agreement AUD	Sep. 30, 2014 Mortgage facilities USD ($)	Dec. 31, 2013 Mortgage facilities USD ($)	Sep. 30, 2014 Other Debt Securities USD ($)	Dec. 31, 2013 Other Debt Securities USD ($)
Long Term Debt
Long-term Debt	$ 1,233.4	$ 1,083.2		$ 174.0	$ 90.0		$ 98.0	$ 98.0	$ 136.2		$ 106.0				$ 21.9	$ 29.8						$ 550.0	$ 550.0			$ 110.0	$ 86.9				$ 130.9	$ 118.6	$ 12.4	$ 3.9
Less: current portion	(71.8)	(50.0)
Net long-term debt	1,161.6	1,033.2
Interest rate (as a percent)																						5.75%	5.75%	5.75%
Initial borrowing capacity			375
Line of credit basis spread on variable rate before amendment of agreement(as a percent)			2.25%
Maximum credit available			450.0			98.0				100.0							30.0			10.0						200.0			25.9	28.0
Base rate of interest on loans			LIBOR			LIBOR			LIBOR	LIBOR										Bank of England Base Rate						three-month LIBOR		30-day Bill Rate
Line of credit basis spread on variable rate (as a percent)			2.00%			2.00%						1.35%	3.00%							1.75%						2.50%		2.35%
Incremental interest rate for uncollateralized borrowings in excess of maximum limit (as a percent)			1.50%
Balance outstanding under credit agreement				174.0			98.0		136.2	84.0				13.5	21.9											110.0		0			130.9
Repayment of term loan, quarterly installments														1.5
Frequency of principal repayments														Quarterly
Final payment due December 31, 2015														7.5
Low end of interest rate, depending on UK subsidiaries ratios (as a percent)																		2.675%
High end of interest rate, depending on UK subsidiaries ratios (as a percent)																			4.325%
Debt issued																					$ 550.0
Specified equity offerings, percentage of debt which may be redeemed																									40.00%
Change of control, redemption price as a percentage of principal																					101.00%
Sale of assets, redemption price as percentage of principal																					100.00%
Domestic Subsidiaries ownership guaranteeing obligations (as a percent)																						100.00%