Income Taxes - Summary of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Deferred tax assets:
Accrued expenses	$ 7,547	$ 8,638
Employee benefits other than pension	23,272	34,147
Lease liabilities	9,415	0
Deferred revenue	30,715	22,351
Pension obligations	27,407	26,821
Tax loss carryforwards	54,556	70,340
Incentive consideration	6,722	9,456
Tax credit carryforwards	16,136	31,467
Suspended loss	14,635	14,474
Other	5,916	8,008
Total deferred tax assets	196,321	225,702
Deferred tax liabilities:
Right of use assets	(9,261)	0
Depreciation and amortization	(7,059)	(13,298)
Software developed for internal use	(66,918)	(103,631)
Intangible assets	(120,528)	(122,921)
Unrealized gains and losses	(18,778)	(21,840)
Non U.S. operations	(13,789)	(9,355)
Investment in partnership	(7,306)	(6,794)
Total deferred tax liabilities	(243,639)	(277,839)
Valuation allowance	(38,272)	(59,294)
Net deferred tax (liability)	$ (85,590)	$ (111,431)