Condensed Consolidated Financial Statements - Additional Information (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
Condensed Financial Statements, Captions [Line Items]
Other current assets	$ 52,259		$ 14,260
Other current liabilities	81,156		61,688
Settlement assets	613,290		32,256
Settlement liabilities	589,742		31,605
Amount of off balance sheet settlement funds	203,200		256,500
Right-of-use assets	62,316		0
Operating lease liability	$ 65,743
Accounting Standards Update 2016-02
Condensed Financial Statements, Captions [Line Items]
Right-of-use assets		$ 63,300
Operating lease liability		$ 68,600
Level 2 | Senior Notes | 5.750% Senior Notes due 2026
Condensed Financial Statements, Captions [Line Items]
Stated interest rate (percentage)	5.75%
Fair value of long-term debt	$ 418,000		395,000
Prior Period Adjustment
Condensed Financial Statements, Captions [Line Items]
Other current assets			(32,300)
Other current liabilities			(31,600)
Settlement assets			32,300
Settlement liabilities			$ 31,600