Other Short-term Borrowings and Long-term Debt - Principal Payments on Long-term Debt (Details) $ in Thousands	Dec. 31, 2022 USD ($)
Debt Instrument [Line Items]
2023	$ 500,000
2024	2,775,000
2025	350,000
2026	0
2027	0
Thereafter	510,000
Total	4,135,000
Synovus Bank
Debt Instrument [Line Items]
2023	500,000
2024	2,775,000
2025	0
2026	0
2027	0
Thereafter	200,000
Total	3,475,000
Parent Company
Debt Instrument [Line Items]
2023	0
2024	0
2025	350,000
2026	0
2027	0
Thereafter	310,000
Total	$ 660,000

Long-Term Debt, Before Hedge-Related Basis Adjustment

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