The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Goodwill and Other Intangibles - Narratives (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Finite-Lived Intangible Assets, Net
Goodwill	$ 907,295		$ 907,295		$ 910,818
Increase (decrease) in value of balance sheet item due to foreign currency translation	5,973	$ 13,847	(7,929)	$ (38,353)
Amortization of intangible assets	57,600	$ 56,800	111,600	$ 117,300
Real Estate
Finite-Lived Intangible Assets, Net
Foreign currency translation adjustments			(3,500)
Goodwill	$ 878,000		878,000		881,500
Investment Management
Finite-Lived Intangible Assets, Net
Goodwill					$ 29,300
Net intangible assets
Finite-Lived Intangible Assets, Net
Increase (decrease) in value of balance sheet item due to foreign currency translation			$ (16,300)
Minimum
Finite-Lived Intangible Assets, Net
Finite lived intangible assets useful life (in years)			3 years
Maximum
Finite-Lived Intangible Assets, Net
Finite lived intangible assets useful life (in years)			48 years