Geographic Areas - Schedule of Segment Reporting (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Segment Reporting Information [Line Items]
Products	$ 198,827	$ 187,437	$ 560,742	$ 536,781
Services	42,923	37,287	115,396	103,129
Intercompany	26,913	10,295	52,097	38,601
Eliminations	(26,913)	(10,295)	(52,097)	(38,601)
Total revenues	241,750	224,724	676,138	639,910
Total Long-Lived Assets	325,061		325,061		315,799
Income before income taxes	73,195	52,184	201,053	160,839
Total Assets	1,429,030		1,429,030		1,394,612
Eliminations [Member]
Segment Reporting Information [Line Items]
Income before income taxes	(567)	2,930	2,639	6,492
Total Long-Lived Assets Eliminations	(2,926)		(2,926)		(2,927)
Total Assets Eliminations	(27,523)		(27,523)		(17,530)
Western Hemisphere [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Products	101,833	105,836	312,175	301,436
Services	20,397	19,012	55,678	53,208
Intercompany	19,501	8,424	38,856	31,702
Total revenues	141,731	133,272	406,709	386,346
Total Long-Lived Assets	224,653		224,653		216,104
Income before income taxes	34,496	27,086	106,666	71,231
Total Assets	747,194		747,194		803,069
Eastern Hemisphere [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Products	53,894	48,235	151,631	146,715
Services	17,587	11,614	45,578	34,181
Intercompany	7,018	243	10,517	994
Total revenues	78,499	60,092	207,726	181,890
Total Long-Lived Assets	45,519		45,519		43,430
Income before income taxes	25,620	5,597	56,794	43,721
Total Assets	370,270		370,270		316,473
Asia-Pacific [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Products	43,100	33,366	96,936	88,630
Services	4,939	6,661	14,140	15,740
Intercompany	394	1,628	2,724	5,905
Total revenues	48,433	41,655	113,800	110,275
Total Long-Lived Assets	57,815		57,815		59,192
Income before income taxes	13,646	16,571	34,954	39,395
Total Assets	$ 339,089		$ 339,089		$ 292,600