Employee Stock Plans - Schedule Payout for TSR Awards (Detail) - RSU Awards - TSR Awards	Dec. 31, 2019
Disclosure Employee Stock Plans Schedule Payout For T S R Awards Detail [Line Items]
At or above 75th percentile	100.00%
50th percentile	50.00%
30th percentile	25.00%
Below 30th percentile	0.00%

Disclosure employee stock plans schedule payout for TSR awards detail line items.

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Payout percentage at or above TSR percentile ranking of 75th percentile.

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Payout percentage at TSR percentile ranking of 50th percentile.

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Payout percentage at TSR percentile ranking of 30th percentile.

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Payout percentage below TSR percentile ranking of 30th percentile.

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