Reconciliations of Equity - Reconciliations of Total Equity (Detail) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2020		Mar. 31, 2019
Reconciliations of total equity
Beginning Balance		$ 892,496		$ 808,185
Issuance of common stock under stock option plan		155		1,890
Purchase of common stock		(7,243)		(77)
Stock-based and deferred compensation		1,116		(1,360)
Net income		27,539		24,978
Other comprehensive income		(40,389)		4,248
Cash dividends paid:
Common stock		(6,202)		(5,643)
Ending Balance		867,472		832,221
Common Stock [Member]
Reconciliations of total equity
Beginning Balance		26,493		26,309
Issuance of common stock under stock option plan		3		39
Stock-based and deferred compensation		45		93
Cash dividends paid:
Ending Balance		26,541		26,441
Additional Paid-in Capital [Member]
Reconciliations of total equity
Beginning Balance		193,135		182,881
Issuance of common stock under stock option plan		152		1,851
Stock-based and deferred compensation		2,374		1,179
Cash dividends paid:
Ending Balance		195,661		185,911
Treasury Stock [Member]
Reconciliations of total equity
Beginning Balance		(114,139)		(97,389)
Purchase of common stock		(7,243)		(77)
Stock-based and deferred compensation		(1,303)		(2,632)
Cash dividends paid:
Ending Balance		(122,685)		(100,098)
Accumulated Other Comprehensive Income (Loss) [Member]
Reconciliations of total equity
Beginning Balance		(136,170)		(141,483)
Other comprehensive income		(40,376)		4,228
Cash dividends paid:
Ending Balance		(176,546)		(142,580)
Other	[1]			(5,325)
Retained Earnings [Member]
Reconciliations of total equity
Beginning Balance		922,464		837,107
Net income		27,545		24,984
Cash dividends paid:
Common stock		(6,202)		(5,643)
Ending Balance		943,807		861,773
Other	[1]			5,325
Noncontrolling Interest [Member]
Reconciliations of total equity
Beginning Balance		713	[2]	760
Net income		(6)	[2]	(6)
Other comprehensive income		(13)	[2]	20
Cash dividends paid:
Ending Balance		$ 694	[2]	$ 774

[1] Reflects beginning retained earnings adjustment as a result of the Company’s first quarter 2019 adoption of ASU No. 2018-02, Income Statement – Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income.

[2] Reflects the noncontrolling interest in the Company’s China joint venture.