Goodwill and Other Intangible Assets (Goodwill) (Details) $ in Thousands	9 Months Ended
Sep. 30, 2019 USD ($)
Goodwill [Roll Forward]
Balance as of December 31, 2018	$ 57,315
Goodwill acquired during the year (preliminary allocation) and adjustments	430,550
Balance as of September 30, 2019	487,865
Synovus Bank Reporting Unit
Goodwill [Roll Forward]
Balance as of December 31, 2018	32,884
Goodwill acquired during the year (preliminary allocation) and adjustments	430,550
Balance as of September 30, 2019	463,434
Trust Services Reporting Unit
Goodwill [Roll Forward]
Balance as of December 31, 2018	24,431
Goodwill acquired during the year (preliminary allocation) and adjustments	0
Balance as of September 30, 2019	$ 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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- Definition

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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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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