The accordian feature under the debt agreement which allows for additional facility capacity.

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The period in which the lender has the ability to call the debt.

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The maximum amount of debt guaranteed by the Company's U.S. parent company.

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Represents the amount of debt reserved for future U.S. acquisitions.

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Line of credit facility additional interest rate.

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Represents the percentage of the aggregate principal amount of debt instruments that may be redeemed with net proceeds of certain equity offerings.

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Represents the ownership percentage of domestic subsidiaries guaranteeing debt of the Company.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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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.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Long-Term Debt (Details) £ in Millions, $ in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2018 AUD ($)	Dec. 31, 2018 GBP (£)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016
Long Term Debt
Total long-term debt			$ 2,216.7	$ 2,163.2
Less: current portion			(92.0)	(72.8)
Net long-term debt			2,124.7	2,090.4
Scheduled maturities of long-term debt for each of the next five years and thereafter
2019			92.0
2020			329.8
2021			68.6
2022			577.9
2023			179.0
2024 and thereafter			969.4
US Credit Agreement Revolving Credit Line
Long Term Debt
Total long-term debt			30.0	172.0
Maximum credit available			700.0
Balance outstanding under credit agreement			30.0
Revolving loans solely for future U.S. acquisitions			250.0
Future borrowings available for foreign acquisitions			150.0
US Credit Agreement Revolving Credit Line \| LIBOR portion
Long Term Debt
Base rate of interest on loans	LIBOR
Line of credit basis spread on variable rate (as a percent)	2.00%
Incremental interest rate for uncollateralized borrowings in excess of maximum limit (as a percent)	1.50%
UK Credit Agreement Revolving Credit Line
Long Term Debt
Total long-term debt			163.3	47.3
Maximum credit available \| £		£ 150.0
Additional facility capacity under accordian feature \| £		100.0
Balance outstanding under credit agreement		£ 129.4	165.1
UK Credit Agreement Revolving Credit Line \| LIBOR portion
Long Term Debt
Base rate of interest on loans	LIBOR
UK Credit Agreement Revolving Credit Line \| Minimum \| LIBOR portion
Long Term Debt
Line of credit basis spread on variable rate (as a percent)	1.10%
UK Credit Agreement Revolving Credit Line \| Maximum \| LIBOR portion
Long Term Debt
Line of credit basis spread on variable rate (as a percent)	2.10%
UK Credit Agreement Overdraft Line of Credit
Long Term Debt
Total long-term debt			$ 1.8
Senior Subordinated Notes
Long Term Debt
Domestic Subsidiaries ownership guaranteeing obligations (as a percent)	100.00%	100.00%	100.00%
Change of control, redemption price as a percentage of principal	101.00%
Sale of assets, redemption price as percentage of principal	100.00%
5.50% senior subordinated notes due 2026
Long Term Debt
Total long-term debt			$ 495.1	$ 494.4
Interest rate (as a percent)	5.50%	5.50%	5.50%	5.50%	5.50%
Debt issued			$ 500.0
5.50% senior subordinated notes due 2026 \| Debt Redemption Prior to May 15, 2021
Long Term Debt
Percentage of principal amount at which the entity may redeem the notes	100.00%
5.50% senior subordinated notes due 2026 \| Debt Redemption Prior to May 15, 2019
Long Term Debt
Specified equity offerings, percentage of debt which may be redeemed	40.00%
5.375% senior subordinated notes due 2024
Long Term Debt
Total long-term debt			$ 297.6	$ 297.2
Interest rate (as a percent)	5.375%	5.375%	5.375%	5.375%
Debt issued			$ 300.0
5.375% senior subordinated notes due 2024 \| Debt Redemption Prior To December 1, 2019
Long Term Debt
Percentage of principal amount at which the entity may redeem the notes	100.00%
5.75% senior subordinated notes due 2022
Long Term Debt
Total long-term debt			$ 546.8	$ 545.9
Interest rate (as a percent)	5.75%	5.75%	5.75%	5.75%
Debt issued			$ 550.0
3.75% senior subordinated notes due 2020
Long Term Debt
Total long-term debt			$ 297.9	$ 296.5
Interest rate (as a percent)	3.75%	3.75%	3.75%	3.75%
Debt issued			$ 300.0
Percentage of principal amount at which the entity may redeem the notes	100.00%
Australia capital loan agreement
Long Term Debt
Total long-term debt			33.6	$ 39.0
Debt term	5 years
Maximum credit available	$ 50.0
Call period	90 days
Maximum amount of debt guaranteed by the Company's U.S. parent company	$ 50.0
Balance outstanding under credit agreement	$ 47.7		33.6
Australia capital loan agreement \| Australian BBSW 30-Day Bill Rate
Long Term Debt
Base rate of interest on loans	30-day Bill Rate
Line of credit basis spread on variable rate (as a percent)	3.00%
Australia working capital loan agreement
Long Term Debt
Total long-term debt			6.1
Debt term	1 year
Maximum credit available	$ 50.0
Call period	90 days
Maximum amount of debt guaranteed by the Company's U.S. parent company	$ 50.0
Balance outstanding under credit agreement	$ 8.6		6.1
Australia working capital loan agreement \| Australian BBSW 30-Day Bill Rate
Long Term Debt
Base rate of interest on loans	30-day Bill Rate
Line of credit basis spread on variable rate (as a percent)	3.00%
Mortgage facilities
Long Term Debt
Total long-term debt			289.6	235.5
Balance outstanding under credit agreement			289.6
Other debt
Long Term Debt
Total long-term debt			$ 54.9	$ 35.4