The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The number of exercisable share options (fully vested and expected to vest) that may be converted as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

As of the balance sheet date, the weighted-average exercise price (at which grantees can acquire the shares reserved for issuance) for exercisable stock options that are fully vested or expected to vest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

+ Details

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Share-Based Compensation (Grants Under All Synovus Equity Compensation Plan) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of securities to be issued upon vesting of restricted share units	1,072,582
Number of securities to be issued upon exercise of outstanding options	1,741,975
Weighted-average exercise price of outstanding options in column (b)	$ 37.88
Number of shares remaining available for issuance excluding shares reflected in columns (a) and (b)	7,050,823
Options exercised, shares	1,504,783	1,870,516	1,999,195
Options granted	$ 0.00	$ 0.00	$ 17.64
Shareholder Approved Equity Compensation Plans for Shares of Synovus Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of securities to be issued upon vesting of restricted share units	1,072,582
Number of securities to be issued upon exercise of outstanding options	1,741,975
Weighted-average exercise price of outstanding options in column (b)	$ 37.88
Number of shares remaining available for issuance excluding shares reflected in columns (a) and (b)	7,050,823
Non-Shareholder Approved Equity Compensation Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of securities to be issued upon vesting of restricted share units	0
Number of securities to be issued upon exercise of outstanding options	0
Weighted-average exercise price of outstanding options in column (b)	$ 0.00
Number of shares remaining available for issuance excluding shares reflected in columns (a) and (b)	0
2013 Omnibus Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares remaining available for issuance excluding shares reflected in columns (a) and (b)	7,050,823
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of securities to be issued upon vesting of restricted share units	762,767	882,823	581,677	920,426