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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.

No definition available.

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

No definition available.

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Common Equity Tier 1 Risk Based Capital as defined in the regulations.

No definition available.

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

No definition available.

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The minimum Common Equity 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.

No definition available.

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

No definition available.

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Namespace Prefix:	cass_
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The Common Equity 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.

No definition available.

Name:	cass_CommonEquityTierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets
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Common Equity Tier 1 capital divided by risk weighted assets as defined by regulations.

No definition available.

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

No definition available.

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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.

No definition available.

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

No definition available.

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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.

No definition available.

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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.

No definition available.

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Ratio of Tier 1 risk-based capital to risk-weighted assets as defined by regulatory framework.

No definition available.

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Data Type:	dtr-types1:percentItemType
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Amount of total capital as defined by regulatory framework.

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Amount of minimum total risk-based capital required for capital adequacy as defined by regulatory framework.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1B

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Amount of minimum total risk-based capital categorized as well capitalized as defined by regulatory framework for prompt corrective action.

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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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1B

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1

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Amount of Tier 1 leverage capital as defined by regulatory framework.

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Amount of minimum Tier 1 leverage capital required for capital adequacy as defined by regulatory framework.

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Amount of minimum Tier 1 leverage capital categorized as well capitalized as defined by regulatory framework for prompt corrective action.

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Amount of Tier 1 risk-based capital as defined by regulatory framework.

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Amount of minimum Tier 1 risk-based capital required for capital adequacy as defined by regulatory framework.

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Amount of minimum Tier 1 risk-based capital categorized as well capitalized as defined by regulatory framework for prompt corrective action.