Summary of Significant Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2019

Accounting Policies [Abstract]

Summary of Newly Adopted Standards in Unaudited Consolidated Statement of Cash Flows

The following tables present the unaudited consolidated statements of cash flows line items after giving effect to the adoption of ASU 2016-18:

	Nine Months Ended September 30, 2018
	As previously reported			ASU 2016-18 adjustments			As adjusted
Cash flows from operating activities
Net cash provided by operating activities	$	145,849		$	—		$	145,849
Cash flows from investing activities
Purchase of short-term investments from funds held for clients		(137,561	)		(53	)		(137,614	)
Proceeds from maturities of short-term investments from funds held for clients		95,500			—			95,500
Net change in funds held for clients		229,375			(229,375	)		—
Purchases of property and equipment		(44,264	)		—			(44,264	)
Net cash provided by (used in) investing activities		143,050			(229,428	)		(86,378	)
Cash flows from financing activities
Net cash used in financing activities		(249,928	)		—			(249,928	)
Total increase (decrease) in cash, cash equivalents, restricted cash and    restricted cash equivalents		38,971			(229,428	)		(190,457	)
Cash, cash equivalents, restricted cash and restricted cash equivalents
Beginning of period		46,077			1,052,783			1,098,860
End of period	$	85,048		$	823,355		$	908,403