v3.19.3

CUSTOMER FUNDS - Investments within Customer Funds (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 1,122,269
Fair Value	1,122,164
Customer funds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	223,850	$ 99,955
Gross Unrealized Gains	39	14
Gross Unrealized Losses	(63)	(7)
Fair Value	223,826	99,962
Customer funds | U.S. agency securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,657	27,293
Gross Unrealized Gains	0	2
Gross Unrealized Losses	(3)	(4)
Fair Value	1,654	27,291
Customer funds | U.S. government securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	222,193	72,662
Gross Unrealized Gains	39	12
Gross Unrealized Losses	(60)	(3)
Fair Value	$ 222,172	$ 72,671

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