Fair Value Accounting (Financial Instruments Measured At Fair Value On A Recurring Basis) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014		Dec. 31, 2013
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	$ 17,808		$ 6,113
Investment securities available for sale	3,132,402		3,199,358
Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0		0
Investment securities available for sale	26,744		26,716
Private equity investments	0		0
Derivative assets	0		0
Salary stock units	154		1,764
Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	17,808		6,113
Investment securities available for sale	3,103,259		3,170,292
Private equity investments	1,499		1,615
Derivative assets	36,180		40,004
Salary stock units	0		0
Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0		0
Investment securities available for sale	2,399		2,350
Private equity investments	27,495		27,745
Derivative assets	0		0
Salary stock units	0		0
Fair Value, Measurements, Recurring [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	17,808		6,113
Mortgage loans held for sale	50,390		45,384
Investment securities available for sale	3,132,402		3,199,358
Private equity investments	28,994		29,360
Mutual funds held in Rabbi Trusts	11,168		11,246
Derivative assets	36,180		40,004
Trading account liabilities	10,370
Salary stock units	154		1,764
Derivative liabilities	38,354		42,142
Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0		0
Mortgage loans held for sale	0		0
Investment securities available for sale	26,744		26,716
Private equity investments	0		0
Mutual funds held in Rabbi Trusts	11,168		11,246
Derivative assets	0		0
Trading account liabilities	0
Salary stock units	154		1,764
Derivative liabilities	0		0
Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	17,808		6,113
Mortgage loans held for sale	50,390		45,384
Investment securities available for sale	3,103,259		3,170,292
Private equity investments	1,499		1,615
Mutual funds held in Rabbi Trusts	0		0
Derivative assets	36,180		40,004
Trading account liabilities	10,370
Salary stock units	0		0
Derivative liabilities	35,829		39,436
Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0		0
Mortgage loans held for sale	0		0
Investment securities available for sale	2,399		2,350
Private equity investments	27,495		27,745
Mutual funds held in Rabbi Trusts	0		0
Derivative assets	0		0
Trading account liabilities	0
Salary stock units	0		0
Derivative liabilities	2,525		2,706
Fair Value, Measurements, Recurring [Member] | U.S. Treasury Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	17,792		17,791
Fair Value, Measurements, Recurring [Member] | U.S. Treasury Securities [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	17,792		17,791
Fair Value, Measurements, Recurring [Member] | U.S. Treasury Securities [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	0		0
Fair Value, Measurements, Recurring [Member] | U.S. Treasury Securities [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	0		0
Fair Value, Measurements, Recurring [Member] | Securities Issued By U.S. Government Sponsored Enterprises [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	113,320		113,745
Fair Value, Measurements, Recurring [Member] | Securities Issued By U.S. Government Sponsored Enterprises [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	0		0
Fair Value, Measurements, Recurring [Member] | Securities Issued By U.S. Government Sponsored Enterprises [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	113,320		113,745
Fair Value, Measurements, Recurring [Member] | Securities Issued By U.S. Government Sponsored Enterprises [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	0		0
Fair Value, Measurements, Recurring [Member] | Mortgage-Backed Securities Issued By U.S. Government Agencies [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	9,582
Investment securities available for sale	169,219		195,117
Fair Value, Measurements, Recurring [Member] | Mortgage-Backed Securities Issued By U.S. Government Agencies [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0
Investment securities available for sale	0		0
Fair Value, Measurements, Recurring [Member] | Mortgage-Backed Securities Issued By U.S. Government Agencies [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	9,582
Investment securities available for sale	169,219		195,117
Fair Value, Measurements, Recurring [Member] | Mortgage-Backed Securities Issued By U.S. Government Agencies [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0
Investment securities available for sale	0		0
Fair Value, Measurements, Recurring [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	2,385,964		2,421,360
Fair Value, Measurements, Recurring [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	0		0
Fair Value, Measurements, Recurring [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	2,385,964		2,421,360
Fair Value, Measurements, Recurring [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	0		0
Fair Value, Measurements, Recurring [Member] | Collateralized Mortgage Obligations Issued By U.S. Government Sponsored Enterprises [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	2,551		2,465
Investment securities available for sale	393,909		398,540
Fair Value, Measurements, Recurring [Member] | Collateralized Mortgage Obligations Issued By U.S. Government Sponsored Enterprises [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0		0
Investment securities available for sale	0		0
Fair Value, Measurements, Recurring [Member] | Collateralized Mortgage Obligations Issued By U.S. Government Sponsored Enterprises [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	2,551		2,465
Investment securities available for sale	393,909		398,540
Fair Value, Measurements, Recurring [Member] | Collateralized Mortgage Obligations Issued By U.S. Government Sponsored Enterprises [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0		0
Investment securities available for sale	0		0
Fair Value, Measurements, Recurring [Member] | Other U.S. Government Agencies [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	34,393		34,641
Fair Value, Measurements, Recurring [Member] | Other U.S. Government Agencies [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	0		0
Fair Value, Measurements, Recurring [Member] | Other U.S. Government Agencies [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	34,393		34,641
Fair Value, Measurements, Recurring [Member] | Other U.S. Government Agencies [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	0		0
Fair Value, Measurements, Recurring [Member] | State And Municipal Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	40		429
Investment securities available for sale	6,454		6,889
Fair Value, Measurements, Recurring [Member] | State And Municipal Securities [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0		0
Investment securities available for sale	0		0
Fair Value, Measurements, Recurring [Member] | State And Municipal Securities [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	40		429
Investment securities available for sale	6,454		6,889
Fair Value, Measurements, Recurring [Member] | State And Municipal Securities [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0		0
Investment securities available for sale	0		0
Fair Value, Measurements, Recurring [Member] | All Other Mortgage-Backed Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	5,131		968
Fair Value, Measurements, Recurring [Member] | All Other Mortgage-Backed Securities [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0		0
Fair Value, Measurements, Recurring [Member] | All Other Mortgage-Backed Securities [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	5,131		968
Fair Value, Measurements, Recurring [Member] | All Other Mortgage-Backed Securities [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0		0
Fair Value, Measurements, Recurring [Member] | Equity, Mutual Funds, And Other [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	504		2,251
Fair Value, Measurements, Recurring [Member] | Equity, Mutual Funds, And Other [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0		0
Fair Value, Measurements, Recurring [Member] | Equity, Mutual Funds, And Other [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	504		2,251
Fair Value, Measurements, Recurring [Member] | Equity, Mutual Funds, And Other [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0		0
Fair Value, Measurements, Recurring [Member] | Equity Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	7,508		7,584
Fair Value, Measurements, Recurring [Member] | Equity Securities [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	6,968		6,956
Fair Value, Measurements, Recurring [Member] | Equity Securities [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	0		0
Fair Value, Measurements, Recurring [Member] | Equity Securities [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	540		628
Fair Value, Measurements, Recurring [Member] | Other Investments [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	3,843	[1]	3,691	[1]
Fair Value, Measurements, Recurring [Member] | Other Investments [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	1,984	[1]	1,969	[1]
Fair Value, Measurements, Recurring [Member] | Other Investments [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	0	[1]	0	[1]
Fair Value, Measurements, Recurring [Member] | Other Investments [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	1,859	[1]	1,722	[1]
Fair Value, Measurements, Recurring [Member] | Interest Rate Contracts [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	34,924		38,482
Derivative liabilities	35,775		39,436
Fair Value, Measurements, Recurring [Member] | Interest Rate Contracts [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0		0
Derivative liabilities	0		0
Fair Value, Measurements, Recurring [Member] | Interest Rate Contracts [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	34,924		38,482
Derivative liabilities	35,775		39,436
Fair Value, Measurements, Recurring [Member] | Interest Rate Contracts [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0		0
Derivative liabilities	0		0
Fair Value, Measurements, Recurring [Member] | Mortgage Derivatives [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	1,256		1,522
Derivative liabilities	54	[2]
Fair Value, Measurements, Recurring [Member] | Mortgage Derivatives [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0		0
Derivative liabilities	0	[2]
Fair Value, Measurements, Recurring [Member] | Mortgage Derivatives [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	1,256		1,522
Derivative liabilities	54	[2]
Fair Value, Measurements, Recurring [Member] | Mortgage Derivatives [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	0		0
Derivative liabilities	0	[2]
Fair Value, Measurements, Recurring [Member] | Mortgages [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading account liabilities			1,763
Fair Value, Measurements, Recurring [Member] | Mortgages [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading account liabilities			0
Fair Value, Measurements, Recurring [Member] | Mortgages [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading account liabilities			1,763
Fair Value, Measurements, Recurring [Member] | Mortgages [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading account liabilities			0
Fair Value, Measurements, Recurring [Member] | Other Derivative Contracts, Net [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	2,525		2,706
Fair Value, Measurements, Recurring [Member] | Other Derivative Contracts, Net [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	0		0
Fair Value, Measurements, Recurring [Member] | Other Derivative Contracts, Net [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	0		0
Fair Value, Measurements, Recurring [Member] | Other Derivative Contracts, Net [Member] | Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	$ 2,525		$ 2,706

[1] Based on an analysis of the nature and risks of these investments, Synovus has determined that presenting these investments as a single asset class is appropriate.

[2] Mortgage derivatives consist of customer interest rate lock commitments that relate to the potential origination of mortgage loans, which would be classified as held for sale and forward loan sales commitments with third party investors.