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Represents the aggregate of total long-term debt, including current maturities and short-term debt.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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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.

No definition available.

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Weighted average interest rate of short-term debt outstanding calculated at point in time.

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For the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, the maximum amount borrowed at any time during the period.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Name:	us-gaap_ShortTermDebtTypeAxis=us-gaap_CommercialPaperMember
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Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_CommercialPaperMember
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Name:	us-gaap_CreditFacilityAxis=tris_RevolvingCreditAgreement2022Member
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