Revenue from Contracts with Customers (Schedule of Revenue from Contracts with Customers) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Fee revenue and other income:
In-scope of FASB ASC 606 - Invoice processing fees	$ 19,753	$ 17,923	$ 38,817	$ 37,047
In-scope of FASB ASC 606 - Invoice payment fees	6,595	4,738	12,747	11,117
Information services payment and processing revenue	26,348	22,661	51,564	48,164
Bank service fees	530	398	1,024	808
Fee revenue (in-scope of FASB ASC 606)	26,878	23,059	52,588	48,972
Other income (out-of-scope of FASB ASC 606)	109	115	574	1,297
Total fee revenue and other income	$ 26,987	$ 23,174	$ 53,162	$ 50,269