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Financial Instruments and Fair Value Measurements - Narrative (Details) $ in Thousands, £ in Millions	3 Months Ended
	Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($)	Mar. 31, 2021 GBP (£)	Mar. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Derivative [Line Items]
Aggregate notional amount				$ 2,028,500	$ 1,541,400
Net loss from derivatives not designated in hedging relationships	$ 5,700
Currency exchange swap, maturity Apr 2021 \| Not designated as hedging instrument
Derivative [Line Items]
Aggregate notional amount			£ 810.0	1,112,100	$ 0
Interest rate swaps \| Interest expense
Derivative [Line Items]
Unrealized gains (losses) reclassified to income statement	2,500	$ 1,600
Interest rate swap unrealized loss expected to be reclassified within next twelve months				10,200
Cross-currency swaps \| Foreign exchange gains
Derivative [Line Items]
Unrealized gains (losses) reclassified to income statement	$ 1,200	$ 11,400
Cross-currency swap unrealized gains expected to be reclassified within next twelve months				$ 908