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Line of credit facility additional interest rate.

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Represents the redemption price as a percentage of the principal amount at which the debt instrument may be required to be redeemed in the event of a change of control.

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Represents the redemption price as a percentage of the principal amount at which the debt instrument may be required to be repurchased in the event of certain asset sales.

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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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The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

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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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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. 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	1 Months Ended					3 Months Ended
	Apr. 27, 2018	Aug. 31, 2017 USD ($)	May 31, 2016 USD ($)	Nov. 30, 2014 USD ($)	Aug. 31, 2012 USD ($)	Mar. 31, 2018 GBP (£)	Mar. 31, 2018 AUD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Long Term Debt
Total long-term debt								$ 2,221.2	$ 2,163.2
Less: current portion								(84.3)	(72.8)
Net long-term debt								2,136.9	2,090.4
US Credit Agreement Revolving Credit Line
Long Term Debt
Total long-term debt								128.0	172.0
Debt extension term	1 year
Maximum credit available								700.0
Balance outstanding under credit agreement								128.0
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								155.6	47.3
Maximum credit available \| £						£ 150.0
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)						1.35%
UK Credit Agreement Revolving Credit Line \| Maximum \| LIBOR portion
Long Term Debt
Line of credit basis spread on variable rate (as a percent)						3.00%
UK Credit Agreement Overdraft Line of Credit \| Bank of England Base Rate
Long Term Debt
Base rate of interest on loans						Bank of England Base Rate
Line of credit basis spread on variable rate (as a percent)						1.75%
UK Credit Agreement Revolving Credit Line and Overdraft Line Of Credit
Long Term Debt
Balance outstanding under credit agreement						£ 111.0		155.6
5.50% senior subordinated notes due 2026
Long Term Debt
Total long-term debt								$ 494.6	$ 494.4
Interest rate (as a percent)						5.50%	5.50%	5.50%	5.50%
Debt issued			$ 500.0
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 \| 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 \| Maximum \| 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								$ 297.3	$ 297.2
Interest rate (as a percent)						5.375%	5.375%	5.375%	5.375%
Debt issued				$ 300.0
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%
5.375% 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								$ 546.2	$ 545.9
Interest rate (as a percent)						5.75%	5.75%	5.75%	5.75%
Debt issued					$ 550.0
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%
3.75% senior subordinated notes due 2020
Long Term Debt
Total long-term debt								$ 296.8	$ 296.5
Interest rate (as a percent)						3.75%	3.75%	3.75%	3.75%
Debt issued		$ 300.0
Domestic Subsidiaries ownership guaranteeing obligations (as a percent)						100.00%	100.00%	100.00%
Percentage of principal amount at which the entity may redeem the notes		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%
Australia capital loan agreement
Long Term Debt
Total long-term debt								$ 38.1	$ 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							49.6	38.1
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								0.4
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							$ 0.5	0.4
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								214.4	235.5
Balance outstanding under credit agreement								214.4
Other debt
Long Term Debt
Total long-term debt								$ 49.8	$ 35.4