Investments - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Schedule of Equity Method Investments [Line Items]
SERP Investments at fair value	$ 2,687	$ 2,278
CoBank
Schedule of Equity Method Investments [Line Items]
SERP Investments at fair value	9,800	8,700
Other nonoperating income (expense)	$ 4,200	4,200	$ 2,800
Percentage of patronage credit paid in cash	75.00%
Percentage of patronage credit paid in share	25.00%
Valley Network Partnership
Schedule of Equity Method Investments [Line Items]
Ownership interest, percentage	20.00%
Equity Method Investee
Schedule of Equity Method Investments [Line Items]
Revenue from related parties	$ 900	1,000	1,700
Related party costs	$ 2,700	$ 3,000	$ 3,400

Represents the percentage of patronage credits paid in cash by the entity.

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Represents the percentage of patronage credits paid in share by the entity.

+ References

No definition available.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of realized gain (loss) from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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- Definition

Direct costs arising from transactions with related parties who are not affiliates or joint Ventures. These costs are categorized as cost of goods sold.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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- Definition

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.

+ References

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