Shareholders' Equity - Summary of Required Regulatory Capital (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Parent Company
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Risk-Based Capital Ratio (to risk-weighted assets), Amount	$ 744,687	$ 619,746
Tier 1 Capital (to risk-weighted assets), Amount	712,144	592,562
Common Equity Tier 1 Capital (to risk-weighted assets), Amount	641,340	523,832
Leverage (to adjusted average assets), Amount	$ 712,144	$ 592,562
Total Risk-Based Capital Ratio (to risk-weighted assets), Ratio	14.43%	14.24%
Tier 1 Capital (to risk-weighted assets), Ratio	13.80%	13.61%
Common Equity Tier 1 Capital (to risk-weighted assets), Ratio	12.43%	12.04%
Leverage (to adjusted average assets), Ratio	11.16%	10.68%
Total Risk-Based Capital Ratio (to risk-weighted assets), Minimum for Capital Adequacy Purpose, Amount	$ 412,754	$ 348,191
Tier 1 Capital (to risk-weighted assets), Minimum for Capital Adequacy Purpose, Amount	309,566	261,143
Common Equity Tier 1 Capital (to risk-weighted assets), Minimum for Capital, Adequacy Purpose, Amount	232,174	195,858
Leverage (to adjusted average assets), Minimum for Capital Adequacy Purpose, Amount	$ 255,167	$ 221,863
Total Risk-Based Capital Ratio (to risk-weighted assets), Minimum for Capital Adequacy Purpose, Ratio	8.00%	8.00%
Tier 1 Capital (to risk-weighted assets), Minimum for Capital Adequacy Purpose, Ratio	6.00%	6.00%
Common Equity Tier 1 Capital (to risk-weighted assets), Minimum for Capital, Adequacy Purpose, Ratio	4.50%	4.50%
Leverage (to adjusted average assets), Minimum for Capital Adequacy Purpose, Ratio	4.00%	4.00%
Seacoast National Bank (A Wholly Owned Bank Subsidiary)
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Risk-Based Capital Ratio (to risk-weighted assets), Amount	$ 701,093	$ 565,149
Tier 1 Capital (to risk-weighted assets), Amount	668,550	537,965
Common Equity Tier 1 Capital (to risk-weighted assets), Amount	668,550	537,965
Leverage (to adjusted average assets), Amount	$ 668,550	$ 537,965
Total Risk-Based Capital Ratio (to risk-weighted assets), Ratio	13.60%	13.04%
Tier 1 Capital (to risk-weighted assets), Ratio	12.97%	12.41%
Common Equity Tier 1 Capital (to risk-weighted assets), Ratio	12.97%	12.41%
Leverage (to adjusted average assets), Ratio	10.49%	9.72%
Total Risk-Based Capital Ratio (to risk-weighted assets), Minimum for Capital Adequacy Purpose, Amount	$ 412,486	$ 346,780
Tier 1 Capital (to risk-weighted assets), Minimum for Capital Adequacy Purpose, Amount	309,364	260,085
Common Equity Tier 1 Capital (to risk-weighted assets), Minimum for Capital, Adequacy Purpose, Amount	232,023	195,022
Leverage (to adjusted average assets), Minimum for Capital Adequacy Purpose, Amount	$ 255,036	$ 221,432
Total Risk-Based Capital Ratio (to risk-weighted assets), Minimum for Capital Adequacy Purpose, Ratio	8.00%	8.00%
Tier 1 Capital (to risk-weighted assets), Minimum for Capital Adequacy Purpose, Ratio	6.00%	6.00%
Common Equity Tier 1 Capital (to risk-weighted assets), Minimum for Capital, Adequacy Purpose, Ratio	4.50%	4.50%
Leverage (to adjusted average assets), Minimum for Capital Adequacy Purpose, Ratio	4.00%	4.00%
Total Risk-Based Capital Ratio (to risk-weighted assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 515,607	$ 433,475
Tier 1 Capital (to risk-weighted assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	412,486	346,780
Common Equity Tier 1 Capital (to risk-weighted assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	335,145	281,759
Leverage (to adjusted average assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 318,795	$ 276,791
Total Risk-Based Capital Ratio (to risk-weighted assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	10.00%	10.00%
Tier 1 Capital (to risk-weighted assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	8.00%	8.00%
Common Equity Tier 1 Capital (to risk-weighted assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	6.50%	6.50%
Leverage (to adjusted average assets), Minimum To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	5.00%	5.00%

Common equity capital as defined in the regulations. Also called Core Capital.

No definition available.

Name:	sbcf_CommonEquityTierOneLeverageCapital
Namespace Prefix:	sbcf_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The minimum amount of Tier 1 Risk Based common equity capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

+ References

No definition available.

+ Details

Name:	sbcf_CommonEquityTierOneRiskBasedCapitalRequiredForCapitalAdequacy
Namespace Prefix:	sbcf_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The minimum Tier common equity Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

+ References

No definition available.

+ Details

Name:	sbcf_CommonEquityTierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets
Namespace Prefix:	sbcf_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The amount of Tier 1 Risk Based Common Equity Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

+ References

No definition available.

+ Details

Name:	sbcf_CommonEquityTierOneRiskBasedCapitalRequiredToBeWellCapitalized
Namespace Prefix:	sbcf_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The Tier 1 capital ratio (Tier 1 common equity capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

+ References

No definition available.

+ Details

Name:	sbcf_CommonEquityTierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets
Namespace Prefix:	sbcf_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Common equity tier 1 capital divided by risk weighted assets as defined by regulations.

+ References

No definition available.

+ Details

Name:	sbcf_CommonEquityTierOneRiskBasedCapitalToRiskWeightedAssets
Namespace Prefix:	sbcf_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The amount of total capital as defined in the regulations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6490092&loc=d3e47304-110998

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1H
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1H
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=6490092&loc=d3e47080-110998

+ Details

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

- Definition

The minimum amount of Total Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1H
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826

+ Details

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

- Definition

The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1H
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958570-112826

+ Details

Name:	us-gaap_CapitalRequiredForCapitalAdequacyToRiskWeightedAssets
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The amount of Total Capital required to be categorized as well as capitalized under the regulatory framework for prompt corrective action.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826

+ Details

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

- Definition

The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

+ References

+ Details

Name:	us-gaap_CapitalRequiredToBeWellCapitalizedToRiskWeightedAssets
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Total Capital divided by risk weighted assets as defined in the regulations.

+ References

+ Details

Name:	us-gaap_CapitalToRiskWeightedAssets
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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.

+ Details

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

- Definition

Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital.

+ References

+ Details

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

- Definition

The minimum amount of Tier 1 Leverage Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

+ References

+ Details

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

- Definition

The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations.

+ References

+ Details

Name:	us-gaap_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The amount of Tier 1 Leverage Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

+ References

+ Details

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

- Definition

The amount of Tier 1 Leverage Capital required to be categorized as well capitalized divided by average assets as defined in the regulatory framework for prompt corrective action.

+ References

+ Details

Name:	us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Tier 1 Leverage Capital divided by average assets as defined in the regulations.

+ References

+ Details

Name:	us-gaap_TierOneLeverageCapitalToAverageAssets
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Tier 1 Risk Based Capital as defined in the regulations.

+ References

+ Details

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

- Definition

The minimum amount of Tier 1 Risk Based Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

+ References

+ Details

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

- Definition

The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958570-112826

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1H
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826

+ Details

Name:	us-gaap_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The amount of Tier 1 Risk Based Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

+ References

+ Details

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

- Definition

The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

+ References

+ Details

Name:	us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Tier 1 capital divided by risk weighted assets as defined by regulations.

+ References

+ Details

Name:	us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_ConsolidatedEntitiesAxis=us-gaap_ParentCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConsolidatedEntitiesAxis=us-gaap_SubsidiariesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: