Name:	nvl_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisable
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Weighted average price of equity instruments other than options that were either forfeited or expired.

No definition available.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the share-based compensation plan.

No definition available.

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- Details

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Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Aggregate Intrinsic Value, Exercised

No definition available.

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Weighted average price at which instrument holders acquired shares when converting their equity instruments (other than options) into shares.

No definition available.

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Weighted average price at which grantees can acquire the shares reserved for issuance on stock options awarded.

No definition available.

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Intrinsic value of equity-based compensation awards outstanding. Excludes stock and unit options.

No definition available.

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Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of non-option equity instruments exercised by participants.

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Number of shares under non-option equity instrument agreements that were either cancelled or expired.

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Net number of non-option equity instruments granted to participants.

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Data Type:	xbrli:sharesItemType
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Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Details

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Data Type:	num:perShareItemType
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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of fully vested and expected to vest options that are exercisable.

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Data Type:	xbrli:monetaryItemType
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Description of pertinent provisions of equity-based compensation awards that have actual or potential impact upon the company's financial statements.

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Data Type:	xbrli:stringItemType
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Weighted average remaining contractual term of exercisable stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.