Provision for Taxes (Table Text Block)	12 Months Ended
Mar. 31, 2021
Table Text Block [Abstract]
Provision For Taxes	Years Ended March 31, 2021 2020 2019 (In thousands) Pretax earnings: U.S. $ 773,030 $ 372,687 $ 466,175 Non-U.S. 23,628 5,437 11,354 Total pretax earnings $ 796,658 $ 378,124 $ 477,529 Current provision (benefit) Federal $ 100,521 $ (373,817) $ (6,114) State 16,572 (9,600) 3,420 Non-U.S. 3,404 949 1,375 120,497 (382,468) (1,319) Deferred provision (benefit) Federal 53,957 307,846 94,961 State 9,795 9,728 11,311 Non-U.S. 1,553 970 1,719 65,305 318,544 107,991 Provision for income tax expense (benefit) $ 185,802 $ (63,924) $ 106,672 Income taxes paid (net of income tax refunds received) $ 29,044 $ 6,859 $ 4,255
Schedule of Effective Income Tax Rate Reconciliation	Years Ended March 31, 2021 2020 2019 (In percentages) Statutory federal income tax rate 21.00 % 21.00 % 21.00 % Increase (reduction) in rate resulting from: NOL tax rate benefit - % (38.62) % - % State taxes, net of federal benefit 2.53 % 0.02 % 2.41 % Foreign rate differential - % 0.21 % 0.15 % Federal tax credits (0.99) % (0.53) % (0.15) % Transition tax - % - % (0.20) % Tax-exempt income (0.08) % (0.17) % - % Dividend received deduction (0.01) % (0.01) % (0.01) % Other 0.87 % 1.19 % (0.86) % Actual tax expense (benefit) of operations 23.32 % (16.91) % 22.34 %
Components of Deferred Tax Assets and Liabilities	March 31, 2021 2020 Deferred tax assets: (In thousands) Net operating loss and credit carry forwards $ 30,432 $ 25,973 Accrued expenses 109,740 105,171 Policy benefit and losses, claims and loss expenses payable, net 26,799 20,189 Operating leases 19,370 22,353 Total deferred tax assets $ 186,341 $ 173,686 Deferred tax liabilities: Property, plant and equipment $ 1,280,703 $ 1,198,198 Operating leases 19,370 22,353 Deferred policy acquisition costs 13,696 12,795 Unrealized gains 48,667 29,873 Other 2,394 4,010 Total deferred tax liabilities 1,364,830 1,267,229 Net deferred tax liability $ 1,178,489 $ 1,093,543
Reconciliation of Total Amounts of Unrecognized Tax Benefits	Unrecognized Tax Benefits March 31, 2021 2020 (In thousands) Unrecognized tax benefits beginning balance $ 29,632 $ 37,201 Revaluation based on change in after tax benefit - - Additions based on tax positions related to the current year 1,479 42 Reductions for tax positions of prior years (42) (7,606) Settlements - (5) Unrecognized tax benefits ending balance $ 31,069 $ 29,632

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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