Capital Stock - Schedule of Change in Treasury Shares (Detail) - shares	3 Months Ended	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2020
Stockholders Equity Note [Abstract]
Beginning balance	9,807,327	1,808,133
Rabbi trust shares distributed/sold	0	(806)
Shares repurchased	200,000	8,200,000
Ending balance	10,007,327	10,007,327