Fair Value Accounting (Financial Instruments Measured At Fair Value On A Recurring Basis) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013		Dec. 31, 2012		Jun. 30, 2012
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	$ 23,069		$ 11,102
Investment securities available for sale	3,077,706		2,981,112		2,981,112
Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0		0
Investment securities available for sale	4,418		3,205
Private equity investments	0		0
Derivative assets	0		0
Salary stock units	793		1,888
Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	23,069		11,102
Investment securities available for sale	3,069,834		2,974,729
Private equity investments	1,345		1,168
Derivative assets	52,000		64,662
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	3,454		3,178
Private equity investments	29,568		30,708
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	23,069		11,102
Mortgage loans held for sale	112,761		212,663
Investment securities available for sale	3,077,706		2,981,112
Private equity investments	30,913		31,876
Mutual funds held in Rabbi Trusts	10,460		10,001
Derivative assets	52,000		64,662
Trading account liabilities	15,847
Salary stock units			1,888
Derivative liabilities	48,968		66,393
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	4,418		3,205
Private equity investments	0		0
Mutual funds held in Rabbi Trusts	10,460		10,001
Derivative assets	0		0
Trading account liabilities	0
Salary stock units	793		1,888
Derivative liabilities	0		0
Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	23,069		11,102
Mortgage loans held for sale	112,761		212,663
Investment securities available for sale	3,069,834		2,974,729
Private equity investments	1,345		1,168
Mutual funds held in Rabbi Trusts	0		0
Derivative assets	52,000		64,662
Trading account liabilities	15,847
Salary stock units	0		0
Derivative liabilities	45,991		63,437
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	3,454		3,178
Private equity investments	29,568		30,708
Mutual funds held in Rabbi Trusts	0		0
Derivative assets	0		0
Trading account liabilities	0
Salary stock units	0		0
Derivative liabilities	2,977		2,956
Fair Value, Measurements, Recurring [Member] | U.S. Treasury Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities			2,171
Investment securities available for sale	357		356
Fair Value, Measurements, Recurring [Member] | U.S. Treasury Securities [Member] | Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities			0
Investment securities available for sale	357		356
Fair Value, Measurements, Recurring [Member] | U.S. Treasury Securities [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities			2,171
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]
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]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	15,454
Investment securities available for sale	209,561		245,593
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	15,454
Investment securities available for sale	209,561		245,593
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] | Securities Issued By U.S. Government Sponsored Enterprises [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	188,087		293,310
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	188,087		293,310
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 Sponsored Enterprises [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	2,305,351		1,867,493
Trading account liabilities			91
Fair Value, Measurements, Recurring [Member] | Mortgage-Backed 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
Trading account liabilities			0
Fair Value, Measurements, Recurring [Member] | Mortgage-Backed 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	2,305,351		1,867,493
Trading account liabilities			91
Fair Value, Measurements, Recurring [Member] | Mortgage-Backed 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
Trading account liabilities			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	3,072		4,875
Investment securities available for sale	319,515		514,489
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	3,072		4,875
Investment securities available for sale	319,515		514,489
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	36,296		38,046
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	36,296		38,046
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	75		451
Investment securities available for sale	11,024		15,798
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	75		451
Investment securities available for sale	11,024		15,798
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 Residential Mortgage-Backed Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	825		1,159
Fair Value, Measurements, Recurring [Member] | All Other Residential 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 Residential Mortgage-Backed Securities [Member] | Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	825		1,159
Fair Value, Measurements, Recurring [Member] | All Other Residential 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	3,643		2,446
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	3,643		2,446
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	4,953		3,740
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	4,061		2,849
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	892		891
Fair Value, Measurements, Recurring [Member] | Other Investments [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities available for sale	2,562	[1]	2,287	[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	0	[1]	0	[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	2,562	[1]	2,287	[1]
Fair Value, Measurements, Recurring [Member] | Interest Rate Contracts [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative assets	44,790		61,869
Derivative liabilities	45,991		62,912
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	44,790		61,869
Derivative liabilities	45,991		62,912
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	7,210		2,793
Derivative liabilities	0	[2]	525	[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]	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	7,210		2,793
Derivative liabilities	0	[2]	525	[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]	0	[2]
Fair Value, Measurements, Recurring [Member] | Other Derivative Contracts, Net [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative liabilities	2,977		2,956
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	$ 2,977		$ 2,956

[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.