Capital Stock - Summary of Common Stock Activity (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balances (in shares)	(38,526,523)
Stock options exercised (in shares)	198,535	215,724	620,646
Stock options forfeitures, Shares		(4,721)
Ending Balances (in shares)	(38,841,194)	(38,526,523)
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balances (in shares)	(62,081,391)	(62,081,391)	(62,081,391)
Ending Balances (in shares)	(62,081,391)	(62,081,391)	(62,081,391)
Beginning Balances	$ (211,806)	$ (194,953)	$ (172,681)
Ending Balances	$ (229,127)	$ (211,806)	$ (194,953)
Treasury
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balances (in shares)	(23,554,868)	(23,858,463)	(24,344,813)
Ending Balances (in shares)	(23,240,197)	(23,554,868)	(23,858,463)
Beginning Balances	$ (296,390)	$ (296,081)	$ (287,501)
Ending Balances	$ (303,566)	(296,390)	$ (296,081)
Noncontrolling Interest \| Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock Issued During Period, Value, Acquisitions		450
Noncontrolling Interest \| Treasury
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock Issued During Period, Value, Acquisitions		$ 0
Restricted Stock \| Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Restricted stock awards (in shares)	0	0	0
Restricted stock forfeitures (in shares)		0	0
Restricted stock awards	$ (1,253)	$ (1,079)	$ (422)
Share-based compensation expense	7,397	6,504	4,746
Stock compensation awards forfeited, Value	$ (483)	$ (283)	$ (49)
Restricted Stock \| Treasury
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Restricted stock awards (in shares)	96,893	92,401	34,798
Restricted stock forfeitures (in shares)		0	(690)
Restricted stock awards	$ (1,253)	$ (1,079)	$ (422)
Share-based compensation expense	0	0	0
Stock compensation awards forfeited, Value	$ 0	$ 0	$ (6)
Stock Options \| Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock options exercised (in shares)	0	0	0
Stock options forfeitures, Shares		0
Share-based compensation expense	$ 492	$ 272	$ 380
Stock compensation awards forfeited, Value	(5)	(55)
Stock options exercised	$ 5,107	$ 5,738	$ 10,901
Stock Options \| Treasury
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock options exercised (in shares)	193,681	215,724	620,646
Stock options forfeitures, Shares		0
Share-based compensation expense	$ 0	$ 0	$ 0
Stock compensation awards forfeited, Value	0	0
Stock options exercised	$ 2,364	$ 2,835	$ 7,564
Performance Stock \| Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Restricted stock forfeitures (in shares)	0	0
Performance stock issued (in shares)	0	0	0
Share-based compensation expense	$ 6,574	$ 6,186	$ 6,687
Stock compensation awards forfeited, Value	(215)	(385)
Performance stock issued	$ (1,778)	$ (523)	$ (866)
Performance Stock \| Treasury
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Restricted stock forfeitures (in shares)	0	0
Performance stock issued (in shares)	139,478	41,660	72,504
Share-based compensation expense	$ 0	$ 0	$ 0
Stock compensation awards forfeited, Value	0	0
Performance stock issued	$ (1,778)	$ (523)	$ (866)
Employee Stock Purchase Plan \| Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Employee stock purchase plan (in shares)	0	0	0
Employee stock purchase plan	$ 564	$ 478	$ 445
Stock Issued During Period, Value, Acquisitions	$ 921
Employee Stock Purchase Plan \| Treasury
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Employee stock purchase plan (in shares)	5,895	7,725	7,127
Employee stock purchase plan	$ 77	$ 78	$ 87
Stock Compensation Plan \| Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Treasury shares purchased (in shares)	0	0	0
Treasury shares purchased for stock compensation programs	$ 0	$ 0	$ 0
Stock Compensation Plan \| Treasury
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Treasury shares purchased (in shares)	(87,811)	(53,915)	(79,094)
Treasury shares purchased for stock compensation programs	$ (9,301)	$ (4,824)	$ (5,732)
Share Repurchase Program, May 2015 \| Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Treasury shares purchased (in shares)	0		0
Treasury shares purchased for stock compensation programs	$ 0		$ 0
Share Repurchase Program, May 2015 \| Treasury
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Treasury shares purchased (in shares)	33,465		(168,941)
Treasury shares purchased for stock compensation programs	$ 3,347		$ (11,781)
Share Repurchase Program, May 2015 \| Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Treasury shares purchased (in shares)	(33,465)		(168,941)
Share Repurchase Program, May 2015 \| Treasury
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Treasury shares purchased (in shares)	0

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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