Industry Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Fee revenue and other income:
Income from customers	$ 33,662	$ 30,963	$ 65,952	$ 61,732
Intersegment income (expense)
Net income	6,513	5,869	12,820	11,702
Goodwill	12,569	11,590	12,569	11,590	$ 11,590
Other intangible assets, net	2,217	2,201	2,217	2,201
Total assets	1,593,282	1,521,184	1,593,282	1,521,184	$ 1,504,839
Information Services [Member]
Fee revenue and other income:
Income from customers	26,749	24,436	52,395	47,994
Intersegment income (expense)	3,049	2,815	6,013	6,073
Net income	3,932	3,478	7,755	6,425
Goodwill	12,433	11,454	12,433	11,454
Other intangible assets, net	2,217	2,201	2,217	2,201
Total assets	863,562	777,312	863,562	777,312
Banking Services [Member]
Fee revenue and other income:
Income from customers	6,913	6,527	13,557	13,738
Intersegment income (expense)	383	403	744	779
Net income	2,581	2,391	5,065	5,277
Goodwill	136	136	136	136
Other intangible assets, net
Total assets	742,659	753,333	742,659	753,333
Corporate Eliminations and Other [Member]
Fee revenue and other income:
Income from customers
Intersegment income (expense)	(3,432)	(3,218)	(6,757)	(6,852)
Net income
Goodwill
Other intangible assets, net
Total assets	$ (12,939)	$ (9,461)	$ (12,939)	$ (9,461)