Cash, Cash Equivalents and Marketable Securities (Notes)

9 Months Ended

Sep. 30, 2018

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:

	September 30, 2018								December 31, 2017
(in thousands)	Cash & Cash Equivalents			Marketable Securities		Total			Cash & Cash Equivalents			Marketable Securities		Total
Overnight holdings	$	270,172		$	—	$	270,172		$	338,112		$	—	$	338,112
Investments holdings	43,989			37,576		81,565			22,634			1,960		24,594
Cash in demand accounts	29,585			—		29,585			26,700			—		26,700
Outstanding checks	(15,447		)	—		(15,447		)	(33,186		)	—		(33,186		)
Total	$	328,299		$	37,576	$	365,875		$	354,260		$	1,960	$	356,220

Our cash and overnight holdings fluctuate based on the timing of clients’ payroll processing cycles. Included in the cash, cash equivalents and marketable securities at September 30, 2018 and December 31, 2017 are $181.3 million and $271.5 million, respectively, of funds associated with federal and state income tax withholdings, employment taxes and other payroll deductions, as well as $18.0 million and $23.6 million in client prepayments, respectively.