2.2.0.7 false CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) (USD $) 003000 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) true false In Thousands false false 1 USD false false u000 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 u002 Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 u001 Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ false 2 USD false false u000 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 u002 Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 u001 Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ 3 CASH FLOWS FROM OPERATING ACTIVITIES: 1 us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract us-gaap true na duration No definition available. false false false false false true false false false false false false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false xbrli:stringItemType string The net cash from (used in) all of the entity's operating activities, including those of discontinued operations, of the reporting entity. Operating activities include all transactions and events that are not defined as investing or financing activities. Operating activities generally involve producing and delivering goods and providing services. Cash flows from operating activities are generally the cash effects of transactions and other events that enter into the determination of net income. false 4 Net Income (Loss) 2 us-gaap_ProfitLoss us-gaap true credit duration No definition available. false false false false false false false false false false false terselabel false 1 true true false false 35225000 35225 false false false 2 true true false false -3861000 -3861 false false false xbrli:monetaryItemType monetary The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph A1, A4, A5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 5 -Subparagraph b Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 29 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph a Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph c(1) false 5 Adjustments to reconcile net income to net cash from operating activities: 2 nve_AdjustmentsToReconcileNetIncomeToNetCashFromOperatingActivities nve false na duration No definition available. false false false false false true false false false false false false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 6 Depreciation and amortization 3 us-gaap_DepreciationAndAmortization us-gaap true debit duration No definition available. false false false false false false false false false false false false 1 false true false false 165644000 165644 false false false 2 false true false false 158371000 158371 false false false xbrli:monetaryItemType monetary The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 5 false 7 Deferred taxes and deferred investment tax credit 3 us-gaap_DeferredIncomeTaxesAndTaxCredits us-gaap true debit duration No definition available. false false false false false false false false false false false false 1 false true false false 18160000 18160 false false false 2 false true false false 68588000 68588 false false false xbrli:monetaryItemType monetary The net amount of deferred income taxes and income tax credits less the tax benefit from exercise of stock options. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 false 8 AFUDC-equity 3 nve_AllowanceForEquityFunds nve false credit duration Total increase in earnings in the period representing the cost of equity (rate of return) used to finance construction of... false false false false false false false false false false false terselabel false 1 false true false false -13091000 -13091 false false false 2 false true false false -14766000 -14766 false false false xbrli:monetaryItemType monetary Total increase in earnings in the period representing the cost of equity (rate of return) used to finance construction of regulated assets, which is expected to be recovered through rate adjustments. No authoritative reference available. false 9 Deferred energy 3 nve_DeferredEnergyChange nve false credit duration The net change during the reporting period in carrying amount of capitalized fuel costs of a regulated entity that are... false false false false false false false false false false false terselabel false 1 false true false false 92909000 92909 false false false 2 false true false false 141802000 141802 false false false xbrli:monetaryItemType monetary The net change during the reporting period in carrying amount of capitalized fuel costs of a regulated entity that are expected to be recoverable through rate adjustments within one year or the normal operating cycle, if longer. and may include amortization of previously approved deferred energy under/over collection. No authoritative reference available. false 10 Gain on sale of asset 3 us-gaap_GainLossOnSaleOfInvestments us-gaap true credit duration No definition available. false false false false false false false false false false true negated false 1 false true false false -7575000 -7575 false false false 2 false false false false 0 0 false false false xbrli:monetaryItemType monetary The net realized gain or loss on investments sold during the period, which, for cash flow reporting, is a component of proceeds from investing activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 false 11 Other, net 3 us-gaap_AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesOther us-gaap true debit duration No definition available. false false false false false false false false false false false false 1 false true false false 50347000 50347 false false false 2 false true false false 37256000 37256 false false false xbrli:monetaryItemType monetary Transactions that do not result in cash inflows or outflows in the period in which they occur, but affect net income and thus are removed when calculating net cash flow from operating activities using the indirect cash flow method. This element is used when there is not a more specific and appropriate element. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 false 12 Changes in certain assets and liabilities: 2 nve_ChangesInCertainAssetsAndLiabilities nve false na duration No definition available. false false false false false true false false false false false false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 13 Accounts receivable 3 us-gaap_IncreaseDecreaseInAccountsReceivable us-gaap true credit duration No definition available. false false false false false false false false false false false false 1 false true false false -22235000 -22235 false false false 2 false true false false -28876000 -28876 false false false xbrli:monetaryItemType monetary The net change during the reporting period in amount due within one year (or one business cycle) from customers for the credit sale of goods and services. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 false 14 Materials, supplies and fuel 3 us-gaap_IncreaseDecreaseInInventories us-gaap true credit duration No definition available. false false false false false false false false false false false false 1 false true false false 4101000 4101 false false false 2 false true false false 284000 284 false false false xbrli:monetaryItemType monetary The net change during the reporting period in the aggregate value of all inventory held by the reporting entity, associated with underlying transactions that are classified as operating activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 false 15 Other current assets 3 us-gaap_IncreaseDecreaseInOtherOperatingAssets us-gaap true credit duration No definition available. false false false false false false false false false false false false 1 false true false false 5469000 5469 false false false 2 false true false false 5709000 5709 false false false xbrli:monetaryItemType monetary The net change during the reporting period in other operating assets not otherwise defined in the taxonomy. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 false 16 Accounts payable 3 us-gaap_IncreaseDecreaseInAccountsPayable us-gaap true debit duration No definition available. false false false false false false false false false false false false 1 false true false false 8749000 8749 false false false 2 false true false false -26988000 -26988 false false false xbrli:monetaryItemType monetary The net change during the reporting period in the aggregate amount of obligations due within one year (or one business cycle). This may include trade payables, amounts due to related parties, royalties payable, and other obligations. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 false 17 Accrued retirement benefits 3 us-gaap_IncreaseDecreaseInPensionAndPostretirementObligations us-gaap true debit duration No definition available. false false false false false false false false false false true negated false 1 false true false false -9306000 -9306 false false false 2 false true false false -24910000 -24910 false false false xbrli:monetaryItemType monetary The net change during the reporting period in the amount due to fund pension and non-pension benefits to employees, retired and disabled former employees. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 false 18 Other current liabilities 3 us-gaap_IncreaseDecreaseInOtherAccruedLiabilities us-gaap true debit duration No definition available. false false false false false false false false false false false terselabel false 1 false true false false -1790000 -1790 false false false 2 false true false false -14453000 -14453 false false false xbrli:monetaryItemType monetary The net change during the reporting period in other expenses incurred but not yet paid. This element should be used when there is no other more specific or appropriate element. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 false 19 Risk management assets and liabilities 3 nve_RiskManagementAssetsAndLiabilities nve false na duration Net Increase (Decrease) in Derivative Instruments (Assets and Liabilities) false false false false false false false false false false false terselabel false 1 false true false false 5067000 5067 false false false 2 false true false false -2574000 -2574 false false false xbrli:monetaryItemType monetary Net Increase (Decrease) in Derivative Instruments (Assets and Liabilities) No authoritative reference available. false 20 Other deferred assets 3 us-gaap_IncreaseDecreaseInDeferredCharges us-gaap true credit duration No definition available. false false false false false false false false false false false false 1 false true false false -2462000 -2462 false false false 2 false true false false -8653000 -8653 false false false xbrli:monetaryItemType monetary The net change during the reporting period in the value of expenditures made during the current reporting period for benefits that will be received over a period of years. Deferred charges differ from prepaid expenses in that they usually extend over a long period of time and may or may not be regularly recurring costs of operation. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 false 21 Other regulatory assets 3 us-gaap_IncreaseDecreaseInOtherRegulatoryAssets us-gaap true credit duration No definition available. false false false false false false false false false false false false 1 false true false false -23329000 -23329 false false false 2 false true false false -27094000 -27094 false false false xbrli:monetaryItemType monetary The net change during the reporting period in the value of other assets that are created when regulatory agencies permits public utilities to defer costs to the balance sheet. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 false 22 Other deferred liabilities 3 us-gaap_IncreaseDecreaseInOtherDeferredLiability us-gaap true debit duration No definition available. false false false false false false false false false false false false 1 false true false false -4999000 -4999 false false false 2 false true false false -66354000 -66354 false false false xbrli:monetaryItemType monetary The net change during the reporting period in other obligations not otherwise defined in the taxonomy where the payments will be made in future periods. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 false 23 Net Cash from Operating Activities 2 us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations us-gaap true na duration No definition available. false false false false false false false false false false false totallabel false 1 false true false false 300884000 300884 false false false 2 false true false false 193481000 193481 false false false xbrli:monetaryItemType monetary The net cash from (used in) the entity's continuing operations. This element specifically EXCLUDES the cash flows derived by the entity from its discontinued operations, if any. This element is only to be used when the entity reports its cash flows attributable to discontinued operations separately from the cash flow provided by or used in operating activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 26 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 26 -Footnote 10 true 24 CASH FLOWS USED BY INVESTING ACTIVITIES: 1 us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract us-gaap true na duration No definition available. false false false false false true false false false false false false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 25 Additions to Utility Plant (excluding AFUDC-equity) 2 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment us-gaap true credit duration No definition available. false false false false false false false false false false true negated false 1 false true false false -368882000 -368882 false false false 2 false true false false -457483000 -457483 false false false xbrli:monetaryItemType monetary The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 15 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 17 -Subparagraph c false 26 Proceeds from sale of assets 2 us-gaap_ProceedsFromSaleOfOtherPropertyPlantAndEquipment us-gaap true debit duration No definition available. false false false false false false false false false false false false 1 false true false false 18225000 18225 false false false 2 false true false false 0 0 false false false xbrli:monetaryItemType monetary The cash inflow from sale of other property, plant and equipment, used to produce goods or deliver services, and not otherwise defined in the taxonomy. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 15 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 16 -Subparagraph c false 27 Customer advances for construction 2 us-gaap_ProceedsFromAdvancesForConstruction us-gaap true debit duration No definition available. false false false false false false false false false false false false 1 false true false false -5380000 -5380 false false false 2 false true false false -3144000 -3144 false false false xbrli:monetaryItemType monetary The cash inflow from borrowing by the entity from developers, builders, government agencies and municipalities for construction that are repaid in cash, generally on a straight-line basis over periods ranging from five to forty years. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 15, 16 false 28 Contributions in aid of construction 2 us-gaap_ProceedsFromContributionInAidOfConstruction us-gaap true debit duration No definition available. false false false false false false false false false false false false 1 false true false false 35466000 35466 false false false 2 false true false false 29855000 29855 false false false xbrli:monetaryItemType monetary Developers, builders, governmental agencies and municipalities will provide the entity with cash, or in some cases property, to extend its services to their properties. Nonrefundable contributions are recorded as contributions in aid of construction (CIAC) and are amortized as a reduction of the depreciation expense associated with the contributed asset. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 15, 16 false 29 Investments and other property - net 2 us-gaap_PaymentsForProceedsFromOtherInvestingActivities us-gaap true credit duration No definition available. false false false false false false false false false false true negated false 1 false true false false -225000 -225 false false false 2 false true false false -169000 -169 false false false xbrli:monetaryItemType monetary The net cash outflow (inflow) from other investing activities. This element is used when there is not a more specific and appropriate element in the taxonomy. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 15 false 30 Net Cash used by Investing Activities 2 us-gaap_NetCashProvidedByUsedInInvestingActivities us-gaap true debit duration No definition available. false false false false false false false false false false false totallabel false 1 false true false false -320796000 -320796 false false false 2 false true false false -430941000 -430941 false false false xbrli:monetaryItemType monetary The net cash inflow (outflow) from investing activity. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 26 true 31 CASH FLOWS FROM FINANCING ACTIVITIES: 1 us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract us-gaap true na duration No definition available. false false false false false true false false false false false false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 32 Proceeds from issuance of long-term debt 2 us-gaap_ProceedsFromIssuanceOfLongTermDebt us-gaap true debit duration No definition available. false false false false false false false false false false false false 1 false true false false 414279000 414279 false false false 2 false true false false 1036957000 1036957 false false false xbrli:monetaryItemType monetary The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 18 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 19 -Subparagraph b false 33 Retirement of long-term debt 2 us-gaap_RepaymentsOfLongTermDebt us-gaap true credit duration No definition available. false false false false false false false false false false true negated false 1 false true false false -274821000 -274821 false false false 2 false true false false -733761000 -733761 false false false xbrli:monetaryItemType monetary The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 18 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 20 -Subparagraph b false 34 Sale of Common Stock 2 us-gaap_ProceedsFromIssuanceOfCommonStock us-gaap true debit duration No definition available. false false false false false false false false false false false false 1 false true false false 3246000 3246 false false false 2 false true false false 3311000 3311 false false false xbrli:monetaryItemType monetary The cash inflow from the additional capital contribution to the entity. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 18 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 19 -Subparagraph a false 35 Dividends paid 2 us-gaap_PaymentsOfDividends us-gaap true credit duration No definition available. false false false false false false false false false false true negated false 1 false true false false -51693000 -51693 false false false 2 false true false false -46922000 -46922 false false false xbrli:monetaryItemType monetary The cash outflow from the entity's earnings to the shareholders. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 18 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 20 -Subparagraph a false 36 Net Cash from Financing Activities 2 us-gaap_NetCashProvidedByUsedInFinancingActivities us-gaap true debit duration No definition available. false false false false false false false false false false false totallabel false 1 false true false false 91011000 91011 false false false 2 false true false false 259585000 259585 false false false xbrli:monetaryItemType monetary The net cash inflow (outflow) from financing activity for the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 26 true 37 Net Increase in Cash and Cash Equivalents 1 us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease us-gaap true na duration No definition available. false false false false false false false false false false false totallabel false 1 false true false false 71099000 71099 false false false 2 false true false false 22125000 22125 false false false xbrli:monetaryItemType monetary The net change between the beginning and ending balance of cash and cash equivalents. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 26 true 38 Beginning Balance in Cash and Cash Equivalents 1 us-gaap_CashAndCashEquivalentsAtCarryingValue us-gaap true debit instant No definition available. false false false false false false false false true false false periodstartlabel false 1 false true false false 62706000 62706 false false false 2 false true false false 54359000 54359 false false false xbrli:monetaryItemType monetary Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits should not be reported as cash and cash equivalents. 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It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits should not be reported as cash and cash equivalents. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 7, 26 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 8, 9 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 7 -Footnote 1 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 false 41 Cash paid (received) during period for: 2 nve_CashPaidDuringPeriodFor nve false na duration No definition available. false false false false false true false false false false false terselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 42 Interest 3 us-gaap_InterestPaidNet us-gaap true credit duration No definition available. false false false false false false false false false false false false 1 false true false false 163649000 163649 false false false 2 false true false false 154680000 154680 false false false xbrli:monetaryItemType monetary The amount of cash paid during the current period for interest owed on money borrowed, net of interest capitalized. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 29 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 27 -Subparagraph e false 43 Income taxes 3 us-gaap_IncomeTaxesPaidNet us-gaap true credit duration No definition available. false false false false false false false false false false false terselabel false 1 false true false false 14000 14 false false false 2 false true false false 14000 14 false false false xbrli:monetaryItemType monetary The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 29 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 27 -Subparagraph f false 44 Significant non-cash transactions: 2 us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract us-gaap true na duration No definition available. false false false false false true false false false false false terselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false xbrli:stringItemType string Designated to encapsulate the entire footnote disclosure that gives information on the supplemental cash flow activities for noncash (or part noncash) transactions for the period. Noncash is defined as information about all investing and financing activities of an enterprise during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. false 45 Accrued construction expenses as of June 30, 3 us-gaap_NoncashOrPartNoncashAcquisitionFixedAssetsAcquired us-gaap true debit instant No definition available. false false false false false false false false false false false false 1 false true false false 80453000 80453 false false false 2 false true false false 100192000 100192 false false false xbrli:monetaryItemType monetary The amount of fixed assets that an Entity acquires in a noncash (or part noncash) acquisition. Noncash is defined as information about all investing and financing activities of an enterprise during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 32 false 46 Capital lease obligations incurred 3 us-gaap_CapitalLeaseObligationsIncurred us-gaap true credit duration No definition available. false false false false false false false false false false false false 1 true true false false 15336000 15336 false false false 2 true true false false 0 0 false false false xbrli:monetaryItemType monetary The increase during the period in capital lease obligations due to entering into new capital leases. 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