Provision for Taxes (Table Text Block)	12 Months Ended
Mar. 31, 2023
Table Text Block [Abstract]
Provision For Taxes	Earnings before taxes and the provision for taxes consisted of the following: Years Ended March 31, 2023 2022 2021 (In thousands) Pretax earnings: U.S. $ 1,178,264 $ 1,431,155 $ 773,030 Non-U.S. 39,659 44,342 23,628 Total pretax earnings $ 1,217,923 $ 1,475,497 $ 796,658 Current provision Federal $ 115,171 $ 189,488 $ 100,521 State 42,121 55,518 16,572 Non-U.S. 5,150 6,893 3,404 162,442 251,899 120,497 Deferred provision Federal 114,355 90,852 53,957 State 14,077 6,355 9,795 Non-U.S. 4,051 3,105 1,553 132,483 100,312 65,305 Provision for income tax expense $ 294,925 $ 352,211 $ 185,802 Income taxes paid (received) $ 145,680 $( 4,548 )$ 29,044
Schedule of Effective Income Tax Rate Reconciliation	Years Ended March 31, 2023 2022 2021 (In percentages) Statutory federal income tax rate 21.00 % 21.00 % 21.00 % Increase (reduction) in rate resulting from: State taxes, net of federal benefit 3.56 % 3.24 % 2.53 % Foreign rate differential 0.08 % 0.05 % – % Federal tax credits (0.48) % (0.19) % (0.99) % Tax-exempt income (0.08) % (0.03) % (0.08) % Dividend received deduction (0.01) % – % (0.01) % Other 0.15 % (0.20) % 0.87 % Actual tax expense of operations 24.22 % 23.87 % 23.32 %
Components of Deferred Tax Assets and Liabilities	March 31, 2023 2022 Deferred tax assets: (In thousands) Net operating loss and credit carry forwards $ 33,778 $ 36,394 Accrued expenses 112,971 103,723 Policy benefit and losses, claims and loss expenses payable, net 31,436 30,572 Unrealized losses on investments 48,179 – Operating leases 12,058 15,540 Total deferred tax assets $ 238,422 $ 186,229 Deferred tax liabilities: Property, plant and equipment $ 1,545,628 $ 1,405,604 Operating leases 12,175 15,540 Deferred policy acquisition costs 12,038 12,962 Unrealized gains on investments – 36,299 Other 3,008 1,973 Total deferred tax liabilities 1,572,849 1,472,378 Net deferred tax liability$ 1,334,427 $ 1,286,149
Reconciliation of Total Amounts of Unrecognized Tax Benefits	Unrecognized Tax Benefits March 31, 2023 2022 (In thousands) Unrecognized tax benefits beginning balance $ 48,851 $ 31,069 Additions based on tax positions related to the current year 7,226 8,257 Reductions for tax positions of prior years (443) – Additions for tax provisions of prior years 2,473 9,525 Unrecognized tax benefits ending balance$ 58,107 $ 48,851

Tabular disclosure of the components of income tax expense attributable to continuing operations for each year presented including, but not limited to: current tax expense (benefit), deferred tax expense (benefit), investment tax credits, government grants, the benefits of operating loss carryforwards, tax expense that results from allocating certain tax benefits either directly to contributed capital or to reduce goodwill or other noncurrent intangible assets of an acquired entity, adjustments of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity, and adjustments of the beginning-of-the-year balances of a valuation allowance because of a change in circumstances that causes a change in judgment about the realizability of the related deferred tax asset in future years.

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Tabular disclosure of the components of net deferred tax asset or liability recognized in an entity's statement of financial position, including the following: the total of all deferred tax liabilities, the total of all deferred tax assets, the total valuation allowance recognized for deferred tax assets.

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Tabular disclosure of the reconciliation using percentage or dollar amounts of the reported amount of income tax expense attributable to continuing operations for the year to the amount of income tax expense that would result from applying domestic federal statutory tax rates to pretax income from continuing operations.

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Tabular disclosure for tax positions taken in the tax returns filed or to be filed for which it is more likely than not that the tax position will not be sustained upon examination by taxing authorities and other income tax contingencies. Includes, but is not limited to, interest and penalties, reconciliation of unrecognized tax benefits, unrecognized tax benefits that would affect the effective tax rate, tax years that remain subject to examination by tax jurisdictions, and information about positions for which it is reasonably possible that amounts unrecognized will significantly change within 12 months.

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