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Share-Based Employee Compensation (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
May 31, 2025 | Sep. 28, 2025 | Sep. 29, 2024 | Oct. 01, 2023 | Oct. 02, 2022
Del Taco |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Vesting period |  |  |  |  | 1 year
Nonvested restricted stock units |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Vesting period |  | 4 years |  |  |
Awards outstanding (in shares) |  | 543,552 | 381,738 |  |
Total unrecognized compensation cost related to stock options granted |  | $ 12.3 |  |  |
Weighted-average period for unrecognized compensation cost, (in years) |  | 1 year 10 months 24 days |  |  |
Weighted-average grant-date fair value (in usd per share) |  | $ 38.04 | $ 67.74 | $ 68.56 |
Total fair value of awards vested |  | $ 10.4 | $ 8.0 | $ 4.6 |
Modified restricted stock units vested in period (in shares) |  | 146,379 |  |  |
Employee Stock Option |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Vesting period |  | 3 years |  |  |
Total unrecognized compensation cost related to stock options granted |  | $ 0.0 |  |  |
Option grants contractual term |  | 7 years |  |  |
Total intrinsic value of stock options exercised |  | $ 0.0 |  | $ 0.1 |
Performance share awards |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Vesting period | 3 years | 3 years |  |  |
Awards outstanding (in shares) |  | 168,339 | 145,167 |  |
Total unrecognized compensation cost related to stock options granted |  | $ 2.5 |  |  |
Weighted-average period for unrecognized compensation cost, (in years) |  | 2 years 9 months 18 days |  |  |
Weighted-average grant-date fair value (in usd per share) |  | $ 37.11 | $ 70.19 | $ 65.74 |
Total fair value of awards vested |  | $ 0.9 | $ 2.7 | $ 1.8 |
Modified restricted stock units vested in period (in shares) |  | 39,789 |  |  |
Volatility assumption | 42.13% |  |  |  |
Risk-free interest rate | 3.62% |  |  |  |
Dividends yield | 0.00% |  |  |  |
Fair value assumptions, expected term | 3 years |  |  |  |
Share price (in dollars per share) | $ 32.16 |  |  |  |
Restricted Stock [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Total unrecognized compensation cost related to stock options granted |  | $ 0.0 |  |  |
Total fair value of awards vested |  |  |  | $ 0.4 |
Deferred Compensation for Non Management Directors |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Awards outstanding (in shares) |  | 94,834 | 91,885 |  |
Number of trading days |  | 10 days |  |  |
Shares issued in connection with director retirement (in shares) |  | 765 | 765 | 765 |
Minimum | Nonvested restricted stock units |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Restricted stock units vested, percentage |  | 50.00% |  |  |
Minimum | Performance share awards |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Performance share awards vesting rights, percentage | 0.00% | 0.00% |  |  |
Maximum | Performance share awards |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Performance share awards vesting rights, percentage | 200.00% | 150.00% |  |  |
Executive Officers | Nonvested restricted stock units | Share-Based Payment Arrangement, Tranche One |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Vesting period |  | 4 years |  |  |
Awards outstanding (in shares) |  | 4,046 |  |  |
Executive Officers | Nonvested restricted stock units | Share-Based Payment Arrangement, Tranche Two |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Vesting period |  | 3 years |  |  |
Awards outstanding (in shares) |  | 219,954,000 |  |  |
Non-Management Directors | Nonvested restricted stock units |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Vesting period |  | 12 months |  |  |
Awards outstanding (in shares) |  | 84,801 |  |  |
Management | Nonvested restricted stock units |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Vesting period |  | 3 years |  |  |
Awards outstanding (in shares) |  | 234,751 |  |  |
Two Thousand Four Stock Incentive Plan |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Authorized (in shares) |  | 11,600,000 |  |  |
Common stock available for future issuance (in shares) |  | 972,739 |  |  |
Deferred Compensation Plan for Non-Management Directors |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Authorized (in shares) |  | 350,000 |  |  |
Common stock available for future issuance (in shares) |  | 105,811 |  |  |
2023 Omnibus Incentive Plan |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Authorized (in shares) |  | 2,500,000 |  |  |

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- Definition Amount of cost not yet recognized for nonvested award under share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(01) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2)(i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2)(ii) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(02) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iii) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (f)(2)(ii) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition The risk-free interest rate assumption that is used in valuing an option on its own shares. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iv) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition Line items represent financial concepts included in a table. 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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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- Definition Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 718 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (d)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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