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Segment Reporting (Business Segment Assets) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Segment Reporting Information [Line Items]
Goodwill	$ 66,673	$ 66,062
Other intangible assets, net	7,855	7,727
Total assets	5,329,056	4,912,306
Banking [Member]
Segment Reporting Information [Line Items]
Goodwill	48,536	48,536
All Other [Member]
Segment Reporting Information [Line Items]
Goodwill	18,137	17,526
Operating Segment [Member] | Banking [Member]
Segment Reporting Information [Line Items]
Goodwill	48,536	48,536
Other intangible assets, net	18	28
Total assets	5,291,625	4,875,673
Operating Segment [Member] | All Other [Member]
Segment Reporting Information [Line Items]
Goodwill	18,137	17,526
Other intangible assets, net	7,837	7,699
Total assets	$ 37,431	$ 36,633

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