Capital Stock - Narrative (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Capital Unit [Line Items]
Preferred stock, par value (in dollars per share)	$ 50,000	$ 50,000
Cumulative preferred nonvoting stock (as a percent)	4.50%	4.50%
Treasury stock, shares (in shares)	22,804,873	23,013,489
Treasury shares, at cost	$ 330,376	$ 327,756
Common stock, shares authorized (in shares)	180,000,000	180,000,000
Common stock, par value (in dollars per share)	$ 0
Common stock, shares issued (in shares)	62,081,391	62,081,391
Common stock, shares, outstanding (in shares)	39,276,518	39,067,902
Cumulative preferred stock
Capital Unit [Line Items]
Preferred stock, shares authorized (in shares)	100,000
Preferred stock, par value (in dollars per share)	$ 50
Cumulative preferred nonvoting stock (as a percent)	4.50%
Preferred stock, callable price per share (in dollars per share)	$ 52.50
Preferred stock, shares issued (in shares)	71,340	71,340
Treasury stock, shares (in shares)	52,998	52,998
Purchase of treasury shares (in shares)	0	120
Second cumulative preferred voting stock
Capital Unit [Line Items]
Preferred stock, shares authorized (in shares)	1,000,000
Preferred stock, par value (in dollars per share)	$ 10
Preferred stock, shares issued (in shares)	0	0
Common stock
Capital Unit [Line Items]
Purchase of treasury shares (in shares)	0	175,000	33,465
Common stock, shares issued (in shares)	62,081,391	62,081,391
Common stock, value, issued (up to)	$ 100,000
Treasury stock
Capital Unit [Line Items]
Reissued shares (in shares)	246,376	471,681
Preferred stock
Capital Unit [Line Items]
Treasury shares, at cost	$ 1,800