Cash, Cash Equivalents and Investments - Unrestricted and Restricted - (Tables)

3 Months Ended

Mar. 31, 2021

Cash and Cash Equivalents [Abstract]

Summary of Cash, Cash Equivalents and Investments

Our total cash, cash equivalents and investments are summarized below:

	March 31, 2021						December 31, 2020
(in millions)	Cash and cash equivalents		Available-for-sale marketable securities		Total		Cash and cash equivalents		Available-for-sale marketable securities		Total
Cash and cash equivalents	$	500	$	—	$	500	$	301	$	—	$	301
Investments	—		71		71		—		57		57
Restricted cash, cash equivalents and investments:
Payroll funds collected	906		—		906		1,228		—		1,228
Collateral for health benefits claims	22		90		112		16		82		98
Collateral for workers' compensation claims	61		—		61		60		—		60
Other security deposits	2		—		2		2		—		2
Total restricted cash, cash equivalents and investments	991		90		1,081		1,306		82		1,388
Investments, noncurrent	—		130		130		—		138		138
Restricted cash, cash equivalents and investments, noncurrent
Collateral for workers' compensation claims	30		154		184		36		174		210
Total	$	1,521	$	445	$	1,966	$	1,643	$	451	$	2,094