Long-term Debt and Short-term Borrowings (Principal Payments on Long-term Debt) (Details) - USD ($) $ in Thousands	Jan. 22, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
2016		$ 50,079
2017		753,425
2018		250,089
2019		525,090
2020		350,092
Thereafter		261,270
Total long-term debt		2,190,045
Parent Company [Member]
Debt Instrument [Line Items]
2016		0
2017		403,337
2018		0
2019		300,000
2020		0
Thereafter		260,000
Total long-term debt		963,337
Parent Company [Member] \| Subsequent Event [Member] \| 5.125% Subordinated Notes due June 15, 2017 [Member]
Debt Instrument [Line Items]
Repurchase amount	$ 124,700
Synovus Bank [Member]
Debt Instrument [Line Items]
2016		50,079
2017		350,088
2018		250,089
2019		225,090
2020		350,092
Thereafter		1,270
Total long-term debt		$ 1,226,708

Long-term Debt, before Hedge-related Basis Adjustment

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04.(a))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04.(a))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-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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