Nature of Business and Summary of Significant Accounting - Revision of Prior Period Financial Statements and Prior Period Adjustments (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities:
Other current and noncurrent assets and liabilities	$ (31,661)	$ (4,488)	$ (21,739)
Net cash flows from operating activities	220,473	314,895	132,605
Cash flows from financing activities:
Net (decrease) increase in settlement assets and liabilities	(37,834)	101,681	1,127
Net cash flows from financing activities	(256,878)	(159,889)	668,350
Net increase in cash and cash equivalents	(81,240)	124,250	(31,021)
Cash and cash equivalents, including settlement deposits, beginning of period	265,382	141,132	172,153
Cash and cash equivalents, including settlement deposits, end of period	184,142	265,382	141,132
As reported
Cash flows from operating activities:
Other current and noncurrent assets and liabilities		16,919	(16,695)
Net cash flows from operating activities		336,302	137,649
Cash flows from financing activities:
Net (decrease) increase in settlement assets and liabilities		0	0
Net cash flows from financing activities		(261,570)	667,223
Net increase in cash and cash equivalents		43,976	(27,104)
Cash and cash equivalents, including settlement deposits, beginning of period	165,374	121,398	148,502
Cash and cash equivalents, including settlement deposits, end of period		165,374	121,398
Revision adjustment
Cash flows from operating activities:
Other current and noncurrent assets and liabilities		(21,407)	(5,044)
Net cash flows from operating activities		(21,407)	(5,044)
Cash flows from financing activities:
Net (decrease) increase in settlement assets and liabilities		101,681	1,127
Net cash flows from financing activities		101,681	1,127
Net increase in cash and cash equivalents		80,274	(3,917)
Cash and cash equivalents, including settlement deposits, beginning of period	$ 100,008	19,734	23,651
Cash and cash equivalents, including settlement deposits, end of period		$ 100,008	$ 19,734

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