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The excess (deficit) funded status is measured as the difference between the fair value of plan assets and the benefit obligation based on an actuarial valuation, for funding purposes. The excess (deficit) is based on current projected results of actuarial funding valuations on a solvency basis. Actuarial valuations for funding purposes are subject to revaluation on an annual basis.

No definition available.

Name:	cni_DefinedBenefitPlanFundedSolvencyBasisStatusOfPlan
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Maximum percentage of equity investments allocated to an individual issuer during the period.

No definition available.

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Maximum percentage of equity investments allocated to an industry sector during the period.

No definition available.

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Percentage of bonds issued or guaranteed by Canadian, U.S. or other governments and were of investment grade.

No definition available.

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The expected excess (deficit) funded status is measured as the difference between the fair value of plan assets and the benefit obligation based on an upcoming or future actuarial valuation, for funding purposes. The estimated excess (deficit) is based on current projected results of actuarial funding valuations on a solvency basis. Actuarial valuations for funding purposes are subject to revaluation on an annual basis.

No definition available.

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The expected going concern excess (deficit) funded status is measured as the difference between the fair value of plan assets and the benefit obligation based on an upcoming or future actuarial valuation, for funding purposes. The estimated excess (deficit) is based on current projected results of actuarial funding valuations on a solvency basis. Actuarial valuations for funding purposes are subject to revaluation on an annual basis.

No definition available.

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The going concern excess (deficit) funded status is measured as the difference between the fair value of plan assets and the benefit obligation based on an actuarial valuation, for funding purposes. The excess (deficit) is based on current projected results of actuarial funding valuations on a going concern basis. Actuarial valuations for funding purposes are subject to revaluation on an annual basis.

No definition available.

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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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Target allocation of investments of this type to total plan assets presented on a weighted average basis.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)(i)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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Data Type:	num:percentItemType
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Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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