Long-term Debt and Short-term Borrowings (Principal Payments on Long-term Debt) (Details) $ in Thousands	Dec. 31, 2020 USD ($)
Debt Instrument [Line Items]
2021	$ 0
2022	300,145
2023	400,000
2024	0
2025	0
Thereafter	510,000
Total	1,210,145
Synovus Bank Reporting Unit
Debt Instrument [Line Items]
2021	0
2022	145
2023	400,000
2024	0
2025	0
Thereafter	200,000
Total	600,145
Parent Company
Debt Instrument [Line Items]
2021	0
2022	300,000
2023	0
2024	0
2025	0
Thereafter	310,000
Total	$ 610,000

Long-term Debt, before Hedge-related Basis Adjustment

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04.(a))
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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