CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019
Cash flows from operating activities
Net (loss) income		$ (12,269)	$ 16,208
Adjustments to reconcile net income to net cash provided by (used for) operating activities:
Net unrealized loss		49,737	12,870
Stock-based compensation		12,533	9,703
Depreciation and amortization		64,989	51,697
Debt restructuring and debt issuance cost amortization		2,002	2,095
(Benefit) provision for deferred taxes		(8,830)	3,402
Provision for credit losses		33,987	17,791
Changes in operating assets and liabilities, net of effects of acquisitions:
Accounts receivable and securitized accounts receivable		488,709	(239,658)
Prepaid expenses and other current and other long-term assets		(18,830)	(7,109)
Accounts payable		(200,428)	245,657
Accrued expenses and restricted cash payable		(75,383)	(43,554)
Income taxes		5,822	(1,153)
Other current and other long-term liabilities		(1,816)	2,161
Net cash provided by operating activities		340,223	70,110
Cash flows from investing activities
Purchases of property, equipment and capitalized software		(20,665)	(28,385)
Acquisitions, net of cash		0	(568,426)
Purchases of investment securities		(131)	(140)
Maturities of investment securities		88	85
Net cash used for investing activities		(20,708)	(596,866)
Cash flows from financing activities
Repurchase of share-based awards to satisfy tax withholdings		(8,817)	(9,723)
Proceeds from stock option exercises		1,952	405
Net change in deposits		(143,049)	(136,717)
Net activity on other debt		(84,985)	(57,556)
Borrowings on revolving credit facility		0	863,756
Repayments on revolving credit facility		0	(693,600)
Borrowings on term loans		0	550,000
Repayments on term loans		(16,152)	(15,871)
Debt issuance costs		0	(3,443)
Net change in securitized debt		(6,909)	(1,191)
Net cash (used for) provided by financing activities		(257,960)	496,060
Effect of exchange rates on cash, cash equivalents and restricted cash		(16,543)	1,743
Net change in cash, cash equivalents and restricted cash		45,012	(28,953)
Cash, cash equivalents and restricted cash at beginning of period	[1]	981,381	555,031
Cash, cash equivalents and restricted cash at end of period	[1]	1,026,393	526,078
Supplemental disclosure of non-cash investing and financing activities
Capital expenditures incurred but not paid		3,362	2,046
Cash, Cash Equivalents, Restricted Cash And Restricted Cash Equivalents [Roll Forward]
Cash and cash equivalents at beginning of period	[1]	810,932	541,498
Restricted cash at beginning of period	[1]	170,449	13,533
Cash, cash equivalents and restricted cash at beginning of period	[1]	981,381	555,031
Cash and cash equivalents at end of period	[1]	861,188	387,274
Restricted cash at end of period	[1]	165,205	138,804
Cash, cash equivalents and restricted cash at end of period	[1]	$ 1,026,393	$ 526,078

[1] The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within our condensed consolidated balance sheets to amounts within our condensed consolidated statements of cash flows.
  Three Months Ended March 31,   2020   2019 Cash and cash equivalents at beginning of period $ 810,932
  $ 541,498
Restricted cash at beginning of period 170,449
  13,533
Cash, cash equivalents and restricted cash at beginning of period $ 981,381
  $ 555,031
        Cash and cash equivalents at end of period $ 861,188
  $ 387,274
Restricted cash at end of period 165,205
  138,804
Cash, cash equivalents and restricted cash at end of period $ 1,026,393
  $ 526,078