Allowance for Loan Losses - Schedule of Loan Portfolio, Excluding PCI Loans and Related Allowance (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Recorded Investment
Individually Evaluated for Impairment	$ 35,832	$ 36,700
Collectively Evaluated for Impairment	4,937,076	4,774,080
Total	4,972,908	4,810,780
Associated Allowance
Individually Evaluated for Impairment	1,564	2,728
Collectively Evaluated for Impairment	32,041	29,695
Total	33,605	32,423
PCI Loans
Recorded Investment
Individually Evaluated for Impairment	13,381	14,434
Associated Allowance
Individually Evaluated for Impairment	0	0
Construction & land development
Recorded Investment
Individually Evaluated for Impairment	5,070	211
Collectively Evaluated for Impairment	321,096	443,206
Total	326,166	443,417
Associated Allowance
Individually Evaluated for Impairment	16	22
Collectively Evaluated for Impairment	1,838	2,211
Total	1,854	2,233
Construction & land development \| PCI Loans
Recorded Investment
Individually Evaluated for Impairment	158	151
Associated Allowance
Individually Evaluated for Impairment	0	0
Commercial real estate
Recorded Investment
Individually Evaluated for Impairment	10,445	13,638
Collectively Evaluated for Impairment	2,289,663	2,107,600
Total	2,300,108	2,121,238
Associated Allowance
Individually Evaluated for Impairment	247	369
Collectively Evaluated for Impairment	12,750	10,743
Total	12,997	11,112
Commercial real estate \| PCI Loans
Recorded Investment
Individually Evaluated for Impairment	10,259	10,828
Associated Allowance
Individually Evaluated for Impairment	0	0
Residential real estate
Recorded Investment
Individually Evaluated for Impairment	14,615	19,047
Collectively Evaluated for Impairment	1,392,967	1,302,612
Total	1,407,582	1,321,659
Associated Allowance
Individually Evaluated for Impairment	517	805
Collectively Evaluated for Impairment	7,072	6,970
Total	7,589	7,775
Residential real estate \| PCI Loans
Recorded Investment
Individually Evaluated for Impairment	2,364	2,718
Associated Allowance
Individually Evaluated for Impairment	0	0
Commercial and financial
Recorded Investment
Individually Evaluated for Impairment	5,355	3,322
Collectively Evaluated for Impairment	716,331	718,263
Total	721,686	721,585
Associated Allowance
Individually Evaluated for Impairment	727	1,498
Collectively Evaluated for Impairment	7,624	7,087
Total	8,351	8,585
Commercial and financial \| PCI Loans
Recorded Investment
Individually Evaluated for Impairment	600	737
Associated Allowance
Individually Evaluated for Impairment	0	0
Consumer
Recorded Investment
Individually Evaluated for Impairment	347	482
Collectively Evaluated for Impairment	217,019	202,399
Total	217,366	202,881
Associated Allowance
Individually Evaluated for Impairment	57	34
Collectively Evaluated for Impairment	2,757	2,684
Total	2,814	2,718
Consumer \| PCI Loans
Recorded Investment
Individually Evaluated for Impairment	0	0
Associated Allowance
Individually Evaluated for Impairment	$ 0	$ 0

No definition available.

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

- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118955202&loc=SL82895884-210446

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(7)(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447

+ Details

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

- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

+ Details

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

- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

+ Details

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

- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

+ Details

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

- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5074-111524

+ Details

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

- References

No definition available.

+ Details

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

- Details

Name:	us-gaap_InternalCreditAssessmentAxis=sbcf_PurchasedCreditImpairedLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=sbcf_ConstructionAndLandDevelopmentPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialRealEstatePortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ResidentialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: