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Segments Segments (Segment Balance Sheet Data) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Average Assets	$ 29,616,697	$ 25,213,525
Average Loans, including held for sale	15,915,533	14,243,214
Average Goodwill and other intangible assets	147,370	147,910
Average Deposits	23,497,477	19,909,891
Consumer Segment [Member]
Segment Reporting Information [Line Items]
Average Assets	2,238,473	2,375,326
Average Loans, including held for sale	2,099,784	2,239,100
Average Goodwill and other intangible assets	78,353	79,055
Average Deposits	11,282,164	10,236,257
Commercial Segment [Member]
Segment Reporting Information [Line Items]
Average Assets	10,937,391	9,486,074
Average Loans, including held for sale	10,565,800	9,250,645
Average Goodwill and other intangible assets	67,956	68,109
Average Deposits	9,937,985	7,848,367
Wealth Segment [Member]
Segment Reporting Information [Line Items]
Average Assets	1,406,416	1,288,387
Average Loans, including held for sale	1,395,766	1,276,839
Average Goodwill and other intangible assets	746	746
Average Deposits	2,271,166	1,832,418
Segment Totals [Member]
Segment Reporting Information [Line Items]
Average Assets	14,582,280	13,149,787
Average Loans, including held for sale	14,061,350	12,766,584
Average Goodwill and other intangible assets	147,055	147,910
Average Deposits	23,491,315	19,917,042
Other/Elimination [Member]
Segment Reporting Information [Line Items]
Average Assets	15,034,417	12,063,738
Average Loans, including held for sale	1,854,183	1,476,630
Average Goodwill and other intangible assets	315	0
Average Deposits	$ 6,162	$ (7,151)

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