The maximum amount available for the issuance of letters of credit under the credit facility.

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The accordion 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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Represents the amount of debt reserved future foreign acquisitions.

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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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Number of facilities.

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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	9 Months Ended
	Sep. 30, 2019 GBP (£) item	Sep. 30, 2019 USD ($)	Sep. 30, 2019 AUD ($)	Jul. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Long Term Debt
Total long-term debt		$ 2,379.3			$ 2,216.7
Less: current portion		(96.8)			(92.0)
Net long-term debt		$ 2,282.5			2,124.7
Domestic Subsidiaries ownership guaranteeing obligations (as a percent)	100.00%	100.00%	100.00%
US Credit Agreement Revolving Credit Line
Long Term Debt
Total long-term debt		$ 105.0			30.0
Maximum credit available		700.0		$ 700.0
Revolving loans solely for future U.S. acquisitions		250.0
Future borrowings available for foreign acquisitions		150.0
Maximum amount available for letters of credit				$ 50.0
Balance outstanding under credit agreement		105.0
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		154.9			163.3
Maximum credit available		150.0
Additional facility capacity under accordion feature		100.0
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
UK Credit Agreement Revolving Credit Line and Overdraft Line Of Credit
Long Term Debt
Balance outstanding under credit agreement	£ 126.0	$ 154.9
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		$ 495.6			$ 495.1
Interest rate (as a percent)	5.50%	5.50%	5.50%		5.50%
Principal amount		$ 500.0
5.50% senior subordinated notes due 2026 \| Debt Redemption Prior to May 15, 2021
Long Term Debt
Interest rate (as a percent)	5.50%	5.50%	5.50%
Percentage of principal amount at which the entity may redeem the notes	100.00%
5.50% senior subordinated notes due 2026 \| Debt Instrument Redemption Period On or After May 15, 2021
Long Term Debt
Interest rate (as a percent)	5.50%	5.50%	5.50%
5.50% senior subordinated notes due 2026 \| Debt Redemption Prior to May 15, 2019
Long Term Debt
Interest rate (as a percent)	5.50%	5.50%	5.50%
Percentage of principal amount at which the entity may redeem the notes	40.00%
5.375% senior subordinated notes due 2024
Long Term Debt
Total long-term debt		$ 297.9			$ 297.6
Interest rate (as a percent)	5.375%	5.375%	5.375%		5.375%
Principal amount		$ 300.0
5.375% senior subordinated notes due 2024 \| Debt Redemption Prior To December 1, 2019
Long Term Debt
Interest rate (as a percent)	5.375%	5.375%	5.375%
Percentage of principal amount at which the entity may redeem the notes	100.00%
5.375% senior subordinated notes due 2024 \| Debt Instrument Redemption Period On or After December 1, 2019
Long Term Debt
Interest rate (as a percent)	5.375%	5.375%	5.375%
5.75% senior subordinated notes due 2022
Long Term Debt
Total long-term debt		$ 547.4			$ 546.8
Interest rate (as a percent)	5.75%	5.75%	5.75%		5.75%
Principal amount		$ 550.0
3.75% senior subordinated notes due 2020
Long Term Debt
Total long-term debt		$ 298.9			$ 297.9
Interest rate (as a percent)	3.75%	3.75%	3.75%		3.75%
Principal amount		$ 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		30.9			$ 33.6
Maximum credit available			$ 50.0
Debt term	5 years
Call period	90 days
Maximum amount of debt guaranteed by the Company's U.S. parent company			50.0
Balance outstanding under credit agreement		30.9	45.8
Number of facilities \| item	2
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
Maximum credit available			50.0
Debt term	1 year
Call period	90 days
Maximum amount of debt guaranteed by the Company's U.S. parent company			$ 50.0
Balance outstanding under credit agreement		0.0
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		397.3			289.6
Balance outstanding under credit agreement		397.3
Other debt
Long Term Debt
Total long-term debt		$ 51.4			$ 54.9