Hedge-related Basis Adjustments

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- Definition

Other Notes Payable and Capital Lease Obligations

+ References

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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- Definition

Face (par) amount of debt instrument at time of issuance.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Gross amount of debt extinguished.

+ References

No definition available.

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- Definition

Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
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- Definition

Weighted average interest rate of long-term debt outstanding.

+ References

No definition available.

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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Long-term Debt and Short-term Borrowings (Schedule of Long-term Debt Instruments) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 07, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Long-term debt	$ 2,160,881,000	$ 2,186,893,000
Interest rate at period end	0.08%	0.08%		0.08%
7.875% Senior Notes due February 15, 2019 [Member] \| To be paid at Maturity [Member]
Debt Instrument [Line Items]
Stated percentage	7.875%
Extinguishment of debt, amount	$ 300,000,000
5.75% Subordinated Notes, Due December 15, 2025 [Member]
Debt Instrument [Line Items]
Subordinated notes			$ 250,000,000
Parent Company [Member]
Debt Instrument [Line Items]
Hedge-related basis adjustments	873,000	$ 4,018,000
Long-term debt	834,252,000	960,185,000
Parent Company [Member] \| 5.125% Subordinated Notes due June 15, 2017 [Member]
Debt Instrument [Line Items]
Subordinated notes	$ 278,480,000	402,812,000
Stated percentage	5.125%
Debt, face amount	$ 278,600,000.0	403,300,000.0
Parent Company [Member] \| 7.875% Senior Notes due February 15, 2019 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt	297,763,000	296,711,000
Parent Company [Member] \| 5.75% Subordinated Notes, Due December 15, 2025 [Member]
Debt Instrument [Line Items]
Subordinated notes	247,136,000	$ 246,644,000
Stated percentage		5.75%
Debt, face amount	$ 250,000,000
Parent Company [Member] \| 5.75% Subordinated Notes, Due December 15, 2025 [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	4.182%
Parent Company [Member] \| LIBOR Plus 1.80% debentures, due April 19, 2035 with quarterly interest payments and principal to be paid at maturity (rate of 2.04% and 2.11% at December 31, 2013 and 2012, respectively)
Debt Instrument [Line Items]
Unsecured debt	$ 10,000,000	$ 10,000,000
Debt, face amount	$ 10,000,000
Interest rate at period end	2.76%	2.31%
Parent Company [Member] \| LIBOR Plus 1.80% debentures, due April 19, 2035 with quarterly interest payments and principal to be paid at maturity (rate of 2.04% and 2.11% at December 31, 2013 and 2012, respectively) \| LIBOR [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.80%
Synovus Bank [Member]
Debt Instrument [Line Items]
Long-term debt	$ 1,326,629,000	$ 1,226,708,000
Synovus Bank [Member] \| FHLB Advances [Member]
Debt Instrument [Line Items]
FHLB advances with interest and principal payments due at various maturity dates through 2018	$ 1,325,000,000	$ 1,225,000,000
Weighted average interest rate	0.64%	0.46%
Synovus Bank [Member] \| FHLB Advances [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Stated percentage	0.63%
Synovus Bank [Member] \| FHLB Advances [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Stated percentage	0.66%
Synovus Bank [Member] \| Other Notes Payable and Capital Leases [Member]
Debt Instrument [Line Items]
Other notes payable and capital leases with interest and principal payments due at various maturity dates through 2031	$ 1,629,000	$ 1,708,000
Weighted average interest rate	1.59%