Financial Statement Information Net Assets Held for Sale (Details) € in Thousands, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2019 EUR (€)
Impaired Long-Lived Assets Held and Used [Line Items]
Reedemable NCI, Put Option				$ 24,000	€ 21,000
Redeemable NCI, Call Option				26,000	€ 23,000
Redeemable noncontrolling interest	$ 24,077		$ 24,077	24,077
Goodwill	4,334,725		4,334,725	$ 4,406,535
(Gain on disposal of business) and impairment of net assets held for sale	(249)	$ 15,023
Disposal Group, Including Discontinued Operation, Assets	15,000		15,000
Disposal Group, Including Discontinued Operation, Liabilities	7,000		7,000
Europe [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Disposal Group, Including Discontinued Operation, Goodwill	$ (3,000)		(3,000)
Disposal Group, Held-for-sale, Not Discontinued Operations [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Disposal Group, Continuing Operations, Revenue			$ 81,000