Goodwill and Other Intangible Assets (Goodwill) (Details) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($)
Goodwill [Roll Forward]
Balance as of December 31, 2019	$ 497,267
Goodwill acquired and adjustments during the year	0
Balance as of March 31, 2020	497,267
Community Banking Reporting Unit
Goodwill [Roll Forward]
Balance as of December 31, 2019	256,323
Goodwill acquired and adjustments during the year	0
Balance as of March 31, 2020	256,323
Wholesale Banking Reporting Unit
Goodwill [Roll Forward]
Balance as of December 31, 2019	171,636
Goodwill acquired and adjustments during the year	0
Balance as of March 31, 2020	171,636
Consumer Mortgages Reporting Unit
Goodwill [Roll Forward]
Balance as of December 31, 2019	44,877
Goodwill acquired and adjustments during the year	0
Balance as of March 31, 2020	44,877
Wealth Management Reporting Unit
Goodwill [Roll Forward]
Balance as of December 31, 2019	24,431
Goodwill acquired and adjustments during the year	0
Balance as of March 31, 2020	$ 24,431

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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+ References

No definition available.

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