Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Fair value of all derivative assets designated as fair value hedging instruments.

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Fair value of all derivative assets designated as hedges of net investment in foreign operations.

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Financial Instruments and Fair Value Measurements - Additional Information (Details) - USD ($)	3 Months Ended		12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment charges	$ 10,600,000	$ 3,800,000	$ 0	$ 14,455,000	$ 0
Reclassification adjustment related to derivatives from AOCI to interest expense			2,300,000
Derivatives designated as fair value hedges	0		0	0
Derivative designated to hedges of net investments in foreign operations	0		$ 0	0
Noncontrolling Interests
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment charges	$ 7,600,000	$ 2,700,000
Disposal group, held-for-sale
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment charges				10,600,000
Disposal group, held-for-sale \| Noncontrolling Interests
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment charges				7,600,000
Nonrecurring \| Disposal group, held-for-sale \| Property Classified As Held For Sale At September 30, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment charges				3,800,000
Nonrecurring \| Disposal group, held-for-sale \| Property Classified As Held For Sale At December 31, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment charges				10,600,000
Nonrecurring \| Disposal group, held-for-sale \| Noncontrolling Interests \| Property Classified As Held For Sale At September 30, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment charges				2,700,000
Nonrecurring \| Disposal group, held-for-sale \| Noncontrolling Interests \| Property Classified As Held For Sale At December 31, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Impairment charges				$ 7,600,000