Revenue - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended					9 Months Ended
	Sep. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Mar. 31, 2019	Mar. 31, 2018	Sep. 30, 2020	Sep. 30, 2019
Disaggregation of Revenue [Line Items]
Services	$ 283,423	$ 1,415,803	$ 342,907	$ 1,475,088	$ 1,513,779	$ 870,843	$ 1,033,828
United States
Disaggregation of Revenue [Line Items]
Services	228,255		271,671			703,158	819,347
Canada
Disaggregation of Revenue [Line Items]
Services	20,299		25,895			55,164	72,837
Other
Disaggregation of Revenue [Line Items]
Services	34,869		45,341			112,521	141,644
Food & Beverage
Disaggregation of Revenue [Line Items]
Services	48,153		64,774			152,586	204,743
Retail
Disaggregation of Revenue [Line Items]
Services	39,390		39,420			108,882	111,899
Consumer Products
Disaggregation of Revenue [Line Items]
Services	37,175		38,510			111,371	119,866
Communications
Disaggregation of Revenue [Line Items]
Services	20,227		48,147			58,234	136,819
Automotive
Disaggregation of Revenue [Line Items]
Services	13,399		19,125			51,610	55,857
Technology
Disaggregation of Revenue [Line Items]
Services	41,220		28,148			129,569	84,294
Healthcare
Disaggregation of Revenue [Line Items]
Services	25,120		25,152			71,970	74,403
Financials
Disaggregation of Revenue [Line Items]
Services	22,529		28,054			66,282	81,049
Transportation and Travel/Lodging
Disaggregation of Revenue [Line Items]
Services	9,674		20,541			35,226	65,111
Other
Disaggregation of Revenue [Line Items]
Services	$ 26,536		$ 31,036			$ 85,113	$ 99,787