Cash, Cash Equivalents and Marketable Securities (Notes)

3 Months Ended

Mar. 31, 2021

Cash, Cash Equivalents and Marketable Securities [Abstract]

Cash, Cash Equivalents and Marketable Securities

3. Cash, Cash Equivalents and Marketable Securities

The following table summarizes our cash and investments in cash equivalents and marketable securities held by investment managers and overnight investments:

	March 31, 2021						December 31, 2020
(in thousands)	Cash & Cash Equivalents		Marketable Securities		Total		Cash & Cash Equivalents		Marketable Securities		Total
Overnight holdings	$	432,607	$	—	$	432,607	$	503,221	$	—	$	503,221
Investment holdings	48,278		34,292		82,570		47,992		34,529		82,521
Cash in demand accounts	23,105		—		23,105		33,692		—		33,692
Outstanding checks	(9,213)		—		(9,213)		(30,059)		—		(30,059)
Total	$	494,777	$	34,292	$	529,069	$	554,846	$	34,529	$	589,375

Our cash and overnight holdings fluctuate based on the timing of clients’ payroll processing cycles. Our cash, cash equivalents and marketable securities at March 31, 2021 and December 31, 2020 included $273.5 million and $342.0 million, respectively, of funds associated with federal and state income tax withholdings, employment taxes and other payroll deductions, as well as $58.9 million and $35.3 million, respectively, in client prepayments.