Business Combinations - Narrative (Details) $ in Millions	Aug. 21, 2020 USD ($)	Mar. 13, 2020 USD ($) branch
First Bank of the Palm Beaches
Business Acquisition [Line Items]
Number of branches operated \| branch		2
Percentage of common stock acquired		100.00%
Common stock portion, number of Seacoast stock for each share of stock converted (in shares)		0.2000
Goodwill recognized from acquisition, nondeductible		$ 6.9
Fourth Street Banking Company
Business Acquisition [Line Items]
Percentage of common stock acquired	100.00%
Common stock portion, number of Seacoast stock for each share of stock converted (in shares)	0.1275
Goodwill recognized from acquisition, nondeductible	$ 9.0

per share exchange ratio.

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Number Of Branches

+ References

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other nondeductible expenses.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

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