Software and Other Intangible Assets - Summary of Carrying Amount and Accumulated Amortization of Other Intangible Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 534,084	$ 314,339
Accumulated Amortization	(159,176)	(146,212)
Total	374,908	168,127
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	506,831	297,991
Accumulated Amortization	(143,307)	(131,187)
Total	363,524	166,804
Trademarks and tradenames
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	27,253	16,348
Accumulated Amortization	(15,869)	(15,025)
Total	$ 11,384	$ 1,323