Industry Segment Information (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Fee revenue and other income:
Fee income		$ 26,987	$ 23,174	$ 53,162	$ 50,269
Interest income	[1]	11,594	12,116	22,732	24,938
Interest expense		297	481	628	1,446
Intersegment income (expense)
Tax-equivalized pre-tax income	[1]	9,093	7,052	18,150	16,750
Goodwill		14,262	14,262	14,262	14,262	$ 14,262
Other intangible assets, net		2,993	3,852	2,993	3,852
Total assets		2,272,333	1,828,984	2,272,333	1,828,984	$ 2,203,235
Average funding sources		1,766,939	1,426,680	$ 1,727,205	$ 1,357,822
Tax-equivalent basis tax rate				21.00%	21.00%
Tax-equivalent adjustment		487	474	$ 949	$ 958
Information Services [Member]
Fee revenue and other income:
Fee income		26,098	22,460	51,075	47,900
Interest income	[1]	5,884	4,955	11,393	9,662
Interest expense
Intersegment income (expense)
Tax-equivalized pre-tax income	[1]	6,404	3,437	12,417	8,560
Goodwill		12,433	12,433	12,433	12,433
Other intangible assets, net		532	939	532	939
Total assets		1,062,536	822,684	1,062,536	822,684
Average funding sources		905,983	680,061	872,106	678,945
Banking Services [Member]
Fee revenue and other income:
Fee income		612	640	1,250	1,255
Interest income	[1]	6,563	6,601	12,314	13,885
Interest expense		297	481	628	1,446
Intersegment income (expense)		688	556	1,311	1,081
Tax-equivalized pre-tax income	[1]	3,432	2,981	6,194	5,684
Goodwill		1,829	1,829	1,829	1,829
Other intangible assets, net		2,461	2,913	2,461	2,913
Total assets		1,215,799	1,109,676	1,215,799	1,109,676
Average funding sources		860,956	746,619	855,099	678,877
Corporate, Eliminations and Other [Member]
Fee revenue and other income:
Fee income		277	74	837	1,114
Interest income	[1]	(853)	560	(975)	1,391
Interest expense
Intersegment income (expense)		(688)	(556)	(1,311)	(1,081)
Tax-equivalized pre-tax income	[1]	(743)	634	(461)	2,506
Goodwill
Other intangible assets, net
Total assets		(6,002)	(103,376)	(6,002)	(103,376)
Average funding sources

[1] Presented on a tax-equivalent basis assuming a tax rate of 21% for both 2021 and 2020. The tax-equivalent adjustment was approximately $487,000 and $474,000 f for the Second Quarter of 2021 and 2020, respectively, and $949,000 and $958,000 for the First Half of 2021 and 2020, respectively.