Basis of presentation (Details)	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2020 USD ($) $ / $	Dec. 31, 2019 USD ($) $ / $	Sep. 30, 2019 USD ($) $ / $	Sep. 30, 2020 USD ($) segment $ / $	Sep. 30, 2019 USD ($) $ / $	Dec. 31, 2019 USD ($) $ / $	Jun. 30, 2020	Jan. 01, 2020 USD ($)		Mar. 31, 2019 USD ($)	[2]	Dec. 31, 2018 $ / $
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of operating segments | segment				3
Net monetary assets	$ 1,704,900,000	$ 1,232,600,000		$ 1,704,900,000		$ 1,232,600,000
Cash and cash equivalents	592,400,000	311,000,000.0		592,400,000		311,000,000.0
Goodwill	1,184,400,000	784,600,000		1,184,400,000		784,600,000
Argentina conversion losses				(5,300,000)	$ (10,400,000)
Revenues	970,500,000		$ 928,400,000	2,669,300,000	$ 2,747,400,000
Provision for doubtful accounts	39,500,000	30,200,000		39,500,000		30,200,000
Restricted cash	$ 203,000,000.0	$ 158,000,000.0		$ 203,000,000.0		$ 158,000,000.0
Cumulative effect of change in accounting principle								$ (1,700,000)	[1]	$ 0
Argentina, Pesos | Argentina
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Percent of Consolidated Revenue				5.00%	6.00%
Rate decrease percent	22.00%	37.00%	35.00%	22.00%	35.00%	37.00%
Official exchange rate | $ / $	76.3	59.9	57.5	76.3	57.5	59.9						37.6
Net remeasurement loss				$ (5,300,000)	$ 10,400,000
Net monetary assets	$ 19,600,000			19,600,000
Cash and cash equivalents	9,300,000			9,300,000
Nonmonetary assets	147,000,000.0			147,000,000.0
Goodwill	99,800,000			99,800,000
Equity Securities	0			0
Argentina conversion losses	$ 10,400,000
Devaluation settled rates	100.00%
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of change in accounting principle								(1,700,000)	[1]	$ 28,800,000
Accounting Standards Update 2016-13 | Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of change in accounting principle								$ 1,700,000
Internal Loss AR Rebuild
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Third-party expense				300,000		$ 4,500,000
Revenues			$ 4,000,000.0
Bank fees			300,000
Increase to bad debt expense		$ 6,400,000	$ 13,700,000	9,600,000
Provision for doubtful accounts	$ 18,200,000			18,200,000
Accounts receivable	$ 18,800,000			$ 18,800,000
Percent of Accounts Receivable	97.00%			97.00%
FRANCE
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Percentage of Fair Value in Excess of Carrying Amount							8.00%
Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Percentage of Fair Value in Excess of Carrying Amount							21.00%
Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Percentage of Fair Value in Excess of Carrying Amount							199.00%
Revolving Credit Facility
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Restricted cash	$ 5,000,000.0			$ 5,000,000.0

[1] Effective January 1, 2020, we adopted the provisions of ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. We recognized a cumulative effect adjustment to January 1, 2020 retained earnings as a result of adopting this standard. See Note 1 for further details.

[2] Effective January 1, 2019, we adopted the provisions of ASU 2018-02, Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income. We recognized a cumulative effect adjustment to January 1, 2019 retained earnings as a result of adopting this standard. See Note 1 for further details.