Allowance for Credit Losses (Narratives) (Details) $ in Millions	9 Months Ended
Dec. 31, 2022 USD ($)	Dec. 31, 2021
Receivables [Abstract]
Trade receivable components	2
Historical loss rate	4.00%	6.00%
Allowance for expected credit losses	$ 4.0
Available for sale securities, accrued interest receivable	$ 29.6
Financing Receivable Allowance For Credit Loss Additional Information [Abstract]
Reinsurance paid percentage of total assets	1.00%
Premiums Receivable Gross	$ 4.0
Credit card receivables
Receivables [Abstract]
Average Historical Chargeback Term	For credit card receivables, the Company uses a trailing 13 months average historical chargeback percentage of total credit card receivables to estimate a credit loss reserve. The Company rents equipment to corporate customers in which payment terms are 30 days.
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable Allowance For Credit Loss Additional Information [Abstract]
Modeling of mortgage loans	Loans that management has the intent and ability to hold for the foreseeable future, or until maturity or payoff, are reported at amortized cost. Modeling for the Company‘s mortgage loans is based on inputs most highly correlated to defaults, including loan-to-value, occupancy, and payment history. Historical credit loss experience provides additional support for the estimation of expected credit losses. In assessing the credit losses, the portfolio is reviewed on a collective basis, using loan-specific cash flows to determine the fair value of the collateral in the event of default. Adjustments to this analysis are made to assess loans with a loan-to-value of 65% or greater.

Evaluation and assessment of customer credit worthiness over a specified time.

No definition available.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Ratio of insurance contracts that are subject to reinsurance participation to all contracts in force.

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Includes any additional disclosures related to the credit quality of financing receivables. This may include a description of a credit quality indicator or a description of how the internal risk ratings used by a company relate to the likelihood of loss.

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The gain (loss) resulting from the sale of credit card receivables (portfolios).

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Carrying amount as of the balance sheet date of noncurrent interest earned but not received. Also called accrued interest or accrued interest receivable.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Gross amount, as of the balance sheet date, due the entity from (a) agents and insureds, (b) uncollected premiums and (c) others, before deducting the allowance for doubtful accounts.

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