Executive Stock Plans And Stock-Based Compensation (Stock-Based Compensation Expense And Related Income Tax Benefit Recognized) (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2020
Share-based Payment Arrangement, Additional Disclosure [Abstract]
Total stock-based compensation expense	$ 6,187	$ 6,106	$ 5,631
Income tax benefit recorded on stock-based compensation expense	$ 1,389	$ 1,282	$ 1,182

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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