Condensed Financial Information Of Synovus Financial Corp. (Parent Company Only) (Condensed Statements of Cash Flows) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Operating Activities
Net loss attributable to controlling interest	$ 830,209	$ (60,624)	$ (790,678)
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Share-based compensation	9,333	6,029	7,158
Net cash provided by operating activities	472,131	645,707	910,760
Investing Activities
Purchases of investment securities available for sale	(1,803,738)	(3,309,605)	(1,447,514)
Purchases of premises and equipment	(30,485)	(15,944)	(21,281)
Proceeds from sales of investment securities available for sale	1,139,558	2,002,922	20,704
Net cash provided by investing activities	818,056	2,265,937	800,516
Financing Activities
Transfer of funds to dividend payment agent	(7,853)	0	0
Principal repayments on long-term debt	(491,049)	(601,415)	(678,788)
Purchase of treasury shares	0	0	(21)
Proceeds from issuance of long-term debt	860,000	165,000	740,355
Proceeds from issuance of prepaid common stock purchase contracts	0	0	265,564
Proceeds from issuance of common stock	0	0	769,114
Net cash used in financing activities	(1,185,980)	(2,790,242)	(1,886,737)
Increase (decrease) in cash and funds due from banks	104,207	121,402	(175,461)
Cash and cash equivalents at beginning of year	510,423	389,021	564,482
Cash and cash equivalents at end of year	614,630	510,423	389,021
Income tax payments (refunds), net	7,734	5,113	324,257
Interest paid	(139,505)	(195,589)	(302,199)
Parent Company [Member]
Operating Activities
Net loss attributable to controlling interest	830,209	(60,624)	(790,678)
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Equity in undistributed loss of subsidiaries	(810,817)	55,311	960,647
Deferred income tax (benefit) expense	(48,525)	0	(288,430)
Share-based compensation	0	0	7,158
Net (decrease) increase in other liabilities	23,367	(23,162)	(308,126)
Net (increase) decrease in other assets	(1,255)	(4,780)	412,290
Other, net	(6,337)	(6,912)	(61,934)
Net cash provided by operating activities	(13,358)	(40,167)	(69,073)
Investing Activities
Net investment from (in) subsidiaries	0	10,000	(894,813)
Purchases of investment securities available for sale	0	(18,313)	0
Proceeds from sales of investment securities available for sale	0	49,551	0
Net (increase) decrease in short-term notes receivable from non-bank subsidiaries	49,865	107,944	(204,225)
Net cash provided by investing activities	49,865	149,182	(1,099,038)
Financing Activities
Dividends paid to common and preferred shareholders	(79,856)	(79,813)	(73,896)
Transfer of funds to dividend payment agent	(7,853)	0	0
Principal repayments on long-term debt	(170,801)	(21,701)	(10,425)
Purchase of treasury shares	0	0	(21)
Proceeds from issuance of long-term debt	292,639	0	70,355
Proceeds from issuance of prepaid common stock purchase contracts	0	0	265,503
Proceeds from issuance of common stock	0	0	769,176
Net cash used in financing activities	34,129	(101,514)	1,020,692
Increase (decrease) in cash and funds due from banks	70,636	7,501	(147,419)
Cash and cash equivalents at beginning of year	311,502	304,001	451,420
Cash and cash equivalents at end of year	382,138	311,502	304,001
Income tax payments (refunds), net	7,800	5,100	323,200
Interest paid	$ 51,300	$ 39,800	$ 38,800