Shared-Based Compensation - Schedule of Performance Based Awards Goals with Respect to TSR and ROIC (Detail)	6 Months Ended
Jun. 30, 2018
TSR Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Threshold Performance of Shares, percentage	50.00%
Target Performance of Shares, percentage	100.00%
Maximum Performance of Shares, percentage	150.00%
Threshold Performance, percentage	35.00%
Target Performance, percentage	50.00%
Maximum Performance, percentage	75.00%
ROIC Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Threshold Performance of Shares, percentage	35.00%
Target Performance of Shares, percentage	100.00%
Maximum Performance of Shares, percentage	150.00%
Threshold Performance, percentage	15.50%
Target Performance, percentage	18.00%
Maximum Performance, percentage	19.50%

- Definition

Share based compensation arrangement by share based payment award based on threshold performance achievement percentage.

+ References

No definition available.

+ Details

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- Definition

Share based compensation arrangement by share based payment award percentage of shares issuable based on threshold performance.

+ References

No definition available.

+ Details

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- Definition

Share based compensation arrangement by share-based payment award based on maximum performance achievement percentage.

+ References

No definition available.

+ Details

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- Definition

Share based compensation arrangement by share-based payment award based on target performance achievement percentage.

+ References

No definition available.

+ Details

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- Definition

Share based compensation arrangement by share-based payment award percentage of shares issuable based on maximum performance.

+ References

No definition available.

+ Details

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- Definition

Share based compensation arrangement by share-based payment award, percentage of shares Issuable based on target performance.

+ References

No definition available.

+ Details

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- 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.

+ References

No definition available.

+ Details

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- Details

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- Details

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