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Derivative Financial Instruments - Schedule of Weighted-Average Rates Paid and Received for Interest Rate Swaps Outstanding (Detail) | Jun. 30, 2021
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Weighted Average Interest Rate Paid [Member] |
Short-duration insurance contracts, discounted liabilities [Line Items] |
Fair value hedge loan/lease interest rate swaps | 2.97%
Weighted-Average Interest Rate Received [Member] |
Short-duration insurance contracts, discounted liabilities [Line Items] |
Fair value hedge loan/lease interest rate swaps | 0.09%
Financial Institution Counterparties [Member] | Weighted Average Interest Rate Paid [Member] |
Short-duration insurance contracts, discounted liabilities [Line Items] |
Non-hedging interest rate swaps – financial institution counterparties | 3.82%
Financial Institution Counterparties [Member] | Weighted-Average Interest Rate Received [Member] |
Short-duration insurance contracts, discounted liabilities [Line Items] |
Non-hedging interest rate swaps – financial institution counterparties | 1.82%
Customer Counterparties [Member] | Weighted Average Interest Rate Paid [Member] |
Short-duration insurance contracts, discounted liabilities [Line Items] |
Non-hedging interest rate swaps – customer counterparties | 1.82%
Customer Counterparties [Member] | Weighted-Average Interest Rate Received [Member] |
Short-duration insurance contracts, discounted liabilities [Line Items] |
Non-hedging interest rate swaps – customer counterparties | 3.82%

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- Definition Fair Value Hedge Loan Lease Interest Rate Swaps + References No definition available. + Details
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Namespace Prefix: | cfr_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

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- Definition Non-hedging interest rate swaps + References No definition available. + Details
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Namespace Prefix: | cfr_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

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- Definition Non-hedging interest rate swaps (2) + References No definition available. + Details
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Data Type: | num:percentItemType
Balance Type: | na
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- 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
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- Details
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- Details
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- Details
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Namespace Prefix: |
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Period Type: |

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- Details
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