Securities - Amortized Cost and Fair Value of Securities Available for Sale and Held for Investment (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Amortized cost and fair value of securities available for sale and held to maturity
Amortized Cost, Available for Sale	$ 960,809	$ 798,575
Gross Unrealized Gains, Available for Sale	3,767	3,027
Gross Unrealized Losses, Available for Sale	(14,073)	(10,836)
Fair Value, Available for Sale	950,503	790,766
Amortized Cost, Held to Maturity	372,498	203,525
Gross Unrealized Gains, Held to Maturity	1,753	1,155
Gross Unrealized Losses, Held to Maturity	(4,370)	(1,867)
Fair Value, Held to Maturity	369,881	202,813
U.S. Treasury Securities and obligations of U.S. Government Sponsored Entities [Member]
Amortized cost and fair value of securities available for sale and held to maturity
Amortized Cost, Available for Sale	12,073	3,833
Gross Unrealized Gains, Available for Sale	255	78
Gross Unrealized Losses, Available for Sale	0	0
Fair Value, Available for Sale	12,328	3,911
Mortgage-backed Securities, US Government Sponsored Enterprises [Member]
Amortized cost and fair value of securities available for sale and held to maturity
Amortized Cost, Available for Sale	287,726	192,224
Gross Unrealized Gains, Available for Sale	585	847
Gross Unrealized Losses, Available for Sale	(4,823)	(1,322)
Fair Value, Available for Sale	283,488	191,749
Amortized Cost, Held to Maturity	159,941	64,993
Gross Unrealized Gains, Held to Maturity	704	574
Gross Unrealized Losses, Held to Maturity	(1,243)	(16)
Fair Value, Held to Maturity	159,402	65,551
Collateralized Mortgage Obligations Of US Government Sponsored Entities [Member]
Amortized cost and fair value of securities available for sale and held to maturity
Amortized Cost, Available for Sale	238,805	242,620
Gross Unrealized Gains, Available for Sale	314	470
Gross Unrealized Losses, Available for Sale	(5,065)	(4,900)
Fair Value, Available for Sale	234,054	238,190
Amortized Cost, Held to Maturity	147,208	89,265
Gross Unrealized Gains, Held to Maturity	386	581
Gross Unrealized Losses, Held to Maturity	(2,630)	(406)
Fair Value, Held to Maturity	144,964	89,440
Private mortgage backed securities [Member]
Amortized cost and fair value of securities available for sale and held to maturity
Amortized Cost, Available for Sale	32,780	32,558
Gross Unrealized Gains, Available for Sale	0	0
Gross Unrealized Losses, Available for Sale	(791)	(766)
Fair Value, Available for Sale	31,989	31,792
Amortized Cost, Held to Maturity	6,427
Gross Unrealized Gains, Held to Maturity	0
Gross Unrealized Losses, Held to Maturity	(109)
Fair Value, Held to Maturity	0
Private collateralized mortgage obligations [Member]
Amortized cost and fair value of securities available for sale and held to maturity
Amortized Cost, Available for Sale	67,542	77,965
Gross Unrealized Gains, Available for Sale	563	700
Gross Unrealized Losses, Available for Sale	(816)	(708)
Fair Value, Available for Sale	67,289	77,957
Amortized Cost, Held to Maturity		7,967
Gross Unrealized Gains, Held to Maturity		0
Gross Unrealized Losses, Held to Maturity		(85)
Fair Value, Held to Maturity	6,318	7,882
Collateralized loan obligations [Member]
Amortized cost and fair value of securities available for sale and held to maturity
Amortized Cost, Available for Sale	124,716	124,477
Gross Unrealized Gains, Available for Sale	838	0
Gross Unrealized Losses, Available for Sale	(665)	(1,894)
Fair Value, Available for Sale	124,889	122,583
Amortized Cost, Held to Maturity	41,547	41,300
Gross Unrealized Gains, Held to Maturity	430	0
Gross Unrealized Losses, Held to Maturity	(314)	(1,360)
Fair Value, Held to Maturity	41,663	39,940
Obligations of state and political subdivisions [Member]
Amortized cost and fair value of securities available for sale and held to maturity
Amortized Cost, Available for Sale	63,161	39,119
Gross Unrealized Gains, Available for Sale	622	882
Gross Unrealized Losses, Available for Sale	(895)	(110)
Fair Value, Available for Sale	62,888	39,891
Corporate and other debt securities [Member]
Amortized cost and fair value of securities available for sale and held to maturity
Amortized Cost, Available for Sale	74,121	44,652
Gross Unrealized Gains, Available for Sale	257	37
Gross Unrealized Losses, Available for Sale	(517)	(416)
Fair Value, Available for Sale	73,861	44,273
Fair Value, Held to Maturity	0
Private commercial mortgage backed securities [Member]
Amortized cost and fair value of securities available for sale and held to maturity
Amortized Cost, Available for Sale	37,534	41,127
Gross Unrealized Gains, Available for Sale	111	13
Gross Unrealized Losses, Available for Sale	(473)	(720)
Fair Value, Available for Sale	37,172	$ 40,420
Fair Value, Held to Maturity	0
Commercial mortgage backed securities of U.S. Government Sponsored Entities [Member]
Amortized cost and fair value of securities available for sale and held to maturity
Amortized Cost, Available for Sale	22,351
Gross Unrealized Gains, Available for Sale	222
Gross Unrealized Losses, Available for Sale	(28)
Fair Value, Available for Sale	22,545
Amortized Cost, Held to Maturity	17,375
Gross Unrealized Gains, Held to Maturity	233
Gross Unrealized Losses, Held to Maturity	(74)
Fair Value, Held to Maturity	$ 17,534

No definition available.

Name:	us-gaap_AvailableForSaleSecuritiesAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesAmortizedCost
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of debt securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26610-111562

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 320
-Section 50
-Paragraph 2
-Subparagraph (b)-(g)
-URI http://asc.fasb.org/extlink&oid=6957658&loc=d3e62557-112803

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesDebtSecurities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of accumulated unrealized gain on investments in debt securities classified as held-to-maturity.

+ References

+ Details

Name:	us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingGain
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity.

+ References

+ Details

Name:	us-gaap_HeldToMaturitySecuritiesAccumulatedUnrecognizedHoldingLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount before other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

+ References

No definition available.

+ Details

Name:	us-gaap_HeldToMaturitySecuritiesAmortizedCostBeforeOtherThanTemporaryImpairment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair value of investments in debt securities classified as held-to-maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563

+ Details

Name:	us-gaap_HeldToMaturitySecuritiesFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_DebtSecurityAxis=us-gaap_USTreasuryAndGovernmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtSecurityAxis=us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtSecurityAxis=sbcf_CollateralizedMortgageObligationsOfUsGovernmentSponsoredEntitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtSecurityAxis=sbcf_PrivatelyIssuedMortgageBackedSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtSecurityAxis=us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtSecurityAxis=us-gaap_CollateralizedLoanObligationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtSecurityAxis=us-gaap_USStatesAndPoliticalSubdivisionsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtSecurityAxis=us-gaap_CorporateDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtSecurityAxis=us-gaap_CommercialMortgageBackedSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtSecurityAxis=sbcf_CommercialMortgageBackedSecuritiesOfUsGovernmentSponsoredEntitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: