Capital Stock - Schedule of Change in Treasury Shares (Detail)	3 Months Ended
Mar. 31, 2020 shares
Stockholders Equity Note [Abstract]
Beginning balance	1,808,133
Rabbi trust shares distributed/sold	(806)
Shares repurchased	8,000,000
Ending balance	9,807,327

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration