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Federal Income Taxes (Reconciliation of Federal Income Tax on Income at the Corporate Rate to the Effective Tax Rate) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Tax at statutory rate | $ 106,115 | $ 63,627 | $ 70,642
Tax-advantaged interest | (4,514) | (4,730) | (4,909)
Dividends received deduction | (558) | (514) | (443)
Federal Income Tax Expense Benefit Related to Executive Compensation | 2,469 | 2,246 | 2,985
Federal Income Tax Expense (Benefit) Related to Stock-based Compensation | (693) | (1,846) | (3,253)
Other | (1,346) | (2,150) | (255)
Total federal income tax expense | 101,473 | 56,633 | 64,767
Income available to common stockholders, before tax | $ 495,957 | $ 302,988 | $ 336,390
Effective Income Tax Rate Reconciliation, Percent | 20.50% | 18.70% | 19.30%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent | 21.00% |  |

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- Definition The portion of the difference between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to investment income that is tax advantaged. Tax advantaged investment securities generally are, by statute, tax-reduced, tax-deferred, or tax-free. + References No definition available. + Details
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