Line of Credit Facility, Increased Maximum Borrowing Capacity

No definition available.

Name:	nxt_LineOfCreditFacilityIncreasedMaximumBorrowingCapacity
Namespace Prefix:	nxt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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.

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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- Definition

Amount of obligation for supplier finance program.

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- Definition

Indicates line item in statement of financial position that includes obligation for supplier finance program.

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

No definition available.

+ Details

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Credit facilities and other financing arrangements - Additional Information (Details) - USD ($) $ in Thousands		12 Months Ended
	Sep. 08, 2025	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2024
Debt Instrument [Line Items]
Gain (loss) on extinguishment of debt		$ (5,121)	$ 0	$ 0
Supplied finance program, obligation		$ 213,300
Supplier Finance Program, Obligation, Statement of Financial Position [Extensible Enumeration]		Accounts payable
Credit Facility \| Minimum
Debt Instrument [Line Items]
Quarterly commitment fee on the undrawn portion	0.075%
Credit Facility \| Maximum
Debt Instrument [Line Items]
Quarterly commitment fee on the undrawn portion	0.20%
Letter of Credit \| Minimum
Debt Instrument [Line Items]
Quarterly commitment fee on the undrawn portion	0.875%
Letter of Credit \| Maximum
Debt Instrument [Line Items]
Quarterly commitment fee on the undrawn portion	1.50%
Revolving Credit Facility \| New Credit Agreement \| Line of Credit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing, capacity	$ 1,000,000
Line of credit facility, increased maximum borrowing capacity	250,000
Unamortized debt issuance expense		$ 2,000
Line of credit facility, remaining borrowing capacity		922,100
Revolving Credit Facility \| New Credit Agreement \| Credit Facility
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing, capacity		500,000
Letter of Credit \| New Credit Agreement \| Line of Credit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing, capacity	500,000
Line of credit facility, remaining borrowing capacity		$ 77,900
Bridge Loan \| New Credit Agreement \| Line of Credit
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing, capacity	150,000
Existing Credit Agreement \| New Credit Agreement \| Line of Credit
Debt Instrument [Line Items]
Gain (loss) on extinguishment of debt	$ (5,800)