Schedule of Dividends Paid (Detail) - $ / shares		3 Months Ended					12 Months Ended
	Feb. 20, 2020	Mar. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019		Dec. 31, 2018
Equity [Abstract]
Cash dividend paid per share		$ 0.62	$ 0.62	$ 0.62	$ 0.62	$ 0.62	$ 0.62	$ 2.48		$ 2.46
Cash dividend declared per share	$ 0.62							$ 2.48	[1]	$ 2.48	[1]

[1] On February 20, 2020, the Company declared a dividend of $0.62 per share for the second quarter of 2020. On April 2, 2020, the Company canceled its declared dividend for the second quarter of 2020.