Geographic Areas - Schedule of Segment Reporting (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Segment Reporting Information [Line Items]
Products	$ 176,099	$ 189,914	$ 363,623	$ 361,915
Services	39,177	40,401	77,655	72,473
Intercompany	20,580	13,350	31,967	25,184
Eliminations	(20,580)	(13,350)	(31,967)	(25,184)
Total revenues	215,276	230,315	441,278	434,388
Total Long-Lived Assets	315,815		315,815		$ 322,111
Income before income taxes	52,741	69,215	124,480	127,858
Total Assets	1,446,786		1,446,786		1,449,251
Eliminations [Member]
Segment Reporting Information [Line Items]
Income before income taxes	2,786	1,525	6,444	3,206
Total Long-Lived Assets Eliminations	(2,926)		(2,926)		(2,926)
Total Assets Eliminations	(6,291)		(6,291)		(12,307)
Western Hemisphere [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Products	82,560	115,953	174,375	210,342
Services	21,498	18,381	43,807	35,281
Intercompany	14,770	9,063	24,755	19,355
Total revenues	118,828	143,397	242,937	264,978
Total Long-Lived Assets	216,968		216,968		221,597
Income before income taxes	27,016	36,010	59,964	72,170
Total Assets	718,918		718,918		731,448
Eastern Hemisphere [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Products	60,818	43,814	140,239	97,737
Services	13,617	16,514	25,259	27,991
Intercompany	4,602	3,325	4,823	3,499
Total revenues	79,037	63,653	170,321	129,227
Total Long-Lived Assets	45,318		45,318		45,517
Income before income taxes	13,875	15,827	45,583	31,174
Total Assets	389,371		389,371		375,781
Asia-Pacific [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Products	32,721	30,147	49,009	53,836
Services	4,062	5,506	8,589	9,201
Intercompany	1,208	962	2,389	2,330
Total revenues	37,991	36,615	59,987	65,367
Total Long-Lived Assets	56,455		56,455		57,923
Income before income taxes	9,064	$ 15,853	12,489	$ 21,308
Total Assets	$ 344,788		$ 344,788		$ 354,329