Income Taxes - Summary of Variations Between the Effective and Statutory U.S. Federal Income Tax Rates (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Federal income tax provision at statutory tax rate	[1]	$ 26,439	$ 28,931	$ 51,409
State income tax provision, less applicable federal tax benefit	[1],[2]	367	3,094	1,528
Foreign income taxed at different rates		623	864	(8,075)
U.S. taxation of foreign earnings	[3]	2,349	2,348	(1,054)
Unrecognized tax benefits		2,954	(460)	(47)
Domestic production activities deduction				(1,339)
Nontaxable foreign interest income			(1,179)	(2,073)
U.S. tax reform, net impact	[4]		(375)	10,323
Change in accounting methods	[5]		(3,383)	(893)
Prior years return to provision true-up	[6]	(1,740)	(508)	(266)
Stock based compensation, excess tax benefits		(1,633)	(1,648)	(2,254)
U.S. tax credits	[7]	(6,412)	(1,324)	(1,204)
Non-deductible expenses and other items, net		(149)	304	84
Total	[1]	$ 22,798	$ 26,664	$ 46,139
Percentage of Federal income tax provision at statutory tax rate	[1]	21.00%	21.00%	35.00%
Percentage of state income tax provision, less applicable federal tax benefit	[1],[2]	0.30%	2.20%	1.00%
Percentage of Foreign income taxed at different rates		0.50%	0.60%	(5.50%)
Percentage of U.S. taxation of foreign earnings	[3]	1.90%	1.70%	(0.70%)
Percentage of Unrecognized tax benefits		2.30%	(0.30%)
Percentage of Domestic production activities deduction				(0.90%)
Percentage of Nontaxable foreign interest income			(0.90%)	(1.40%)
Percentage of U.S. tax reform, net impact	[4]		(0.30%)	7.00%
Percentage of Change in accounting methods	[5]		(2.50%)	(0.60%)
Percentage of Prior years return to provision true-up	[6]	(1.40%)	(0.40%)	(0.20%)
Percentage of stock based compensation, excess tax benefits		(1.30%)	(1.20%)	(1.50%)
Percentage of U.S. tax credits	[7]	(5.10%)	(1.00%)	(0.80%)
Non-deductible expenses and other items, net		(0.10%)	0.50%	0.00%
Percentage of Total income tax provision	[1]	18.10%	19.40%	31.40%

[1] The 2018 and 2017 amounts for the noted line items have been retrospectively changed from the amounts originally reported as a result of the Company’s first quarter 2019 change in method of accounting for U.S. inventory valuation from LIFO to FIFO.

[2] Includes incremental state research credits for the tax years 2015 - 2019 that were identified as part of a research and development tax credit study.

[3] Includes cost of global intangible low-taxed income (GILTI) in 2019 and 2018 plus other taxes paid or withheld on cash repatriated from foreign countries in 2019 and 2018.

[4] Does not include state tax impacts, which are included in state income tax provision, less applicable federal tax benefit.

[5] For 2018, amount represents the federal tax rate change due to certain accounting methods that were adopted on the 2017 federal income tax return.  For 2017, amount represents an accounting method change for depreciation.

[6] Certain 2018 and 2017 amounts have been reclassified to conform to the 2019 presentation.

[7] Includes incremental federal research credits for 2015 - 2019 that were identified as part of a research and development tax credit study. Also includes a federal tax rate change due to the classification of certain 2016 and 2017 depreciable fixed assets as deductible research costs.