Investments - Narrative (Details) - USD ($)	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Investments
Other income, net	$ 320,000	$ 14,000
Allowance for credit loss	0
Accrued interest receivable	200,000
Amortization of premiums and discounts on investments	173,000	0
Reclassification out of Accumulated Other Comprehensive Income
Investments
Other income, net	0	0
Other Nonoperating Income (Expense)
Investments
Interest income on investments	300,000
Amortization of premiums and discounts on investments	$ 200,000	0
Other Nonoperating Income (Expense) \| Maximum
Investments
Interest income on investments		$ 100,000

The sum of the periodic adjustments of the differences between securities' face values and purchase prices that are charged against earnings. This is called accretion if the security was purchased at a discount and amortization if it was purchased at premium. As a noncash item, this element is an adjustment to net income when calculating cash provided by or used in operations using the indirect method.

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Interest, dividends, rents, ancillary and other revenues earned but not yet received by the entity on its investments.

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Amount of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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