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Income Taxes - Income Tax Expense Differences from the Amount Computed by Applying the U.S. Federal Income Tax Rate (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Amount |  |  |
U.S. federal income tax expense computed at the statutory rate | $ 109,276 | $ 106,831 | $ 109,938
State tax, net of federal income taxes and tax credit and refunds | 4,989 | 4,636 | 4,808
Net investment expense, low-income housing investment | (3,451) | (2,531) | 1,974
Non-taxable or non-deductible items | (2,745) | (9,383) | (4,976)
Total income taxes | $ 108,069 | $ 99,553 | $ 111,744
Percent |  |  |
U.S. Federal income tax rate (as a percent) | 21.00% | 21.00% | 21.00%
State income/franchise taxes, net of U.S. federal income tax effects (as a percent) | 1.00% | 0.90% | 0.90%
Net investment in low income housing investments (as a percent) | (0.70%) | (0.50%) | 0.40%
Non-taxable or non-deductible items (as a percent) | (0.50%) | (1.90%) | (1.00%)
Actual tax expense rate (as a percent) | 20.80% | 19.50% | 21.40%

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- Definition 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 nondeductible expenses and income (loss) exempt from income taxes. + References No definition available. + Details
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- Definition Percentage 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 nondeductible expenses and income (loss) exempt from income taxes. + References No definition available. + Details
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- Definition 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 net investment expense related to low income housing investments. + References No definition available. + Details
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- Definition Percentage 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 applicable to state and local income tax expense (benefit), net of federal tax expense (benefit). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480738/235-10-S50-1 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 231 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482663/740-10-55-231 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 12A -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-12A Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-12 Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(h)(2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1 + Details
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