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Common Equity Tier 1 ratio as defined in the regulations required to be well capitalized.

No definition available.

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Threshold by which dividends declared exceeds a percentage of net profits in any calendar year.

No definition available.

Name:	sfnc_ThresholdPercentageOfNetProfitsExceededByDividendsDeclaredAnyCalendarYear
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Threshold by which dividends declared exceeds a percentage of net profits in any calendar year, combined with percentage of retained net profits of the preceding year.

No definition available.

Name:	sfnc_ThresholdPercentageOfNetProfitsExceededByDividendsDeclaredCombinedWithPrecedingYear
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Ratio of minimum total risk-based capital to risk-weighted assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI https://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826

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Ratio of total risk-based capital to risk-weighted assets as defined by regulatory framework.

Name:	us-gaap_CapitalToRiskWeightedAssets
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- References

No definition available.

Name:	us-gaap_EquityAbstract
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Amount of dividends that can be declared or paid without approval of regulatory agency.

No definition available.

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Ratio of minimum Tier 1 leverage capital to average assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.

Name:	us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets
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Ratio of minimum Tier 1 risk-based capital to risk-weighted assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.