Segments and Geographic Information - Operations by Geographic Location (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Revenues	$ 1,286,340	$ 1,327,523	$ 1,263,460
Long-Lived assets	162,858	170,500
Goodwill	195,733	193,831	199,802
Other Items [Member]
Segment Reporting Information [Line Items]
Revenues	99
Long-Lived assets	10,758
Americas [Member]
Segment Reporting Information [Line Items]
Goodwill	186,049	193,831	199,802
Americas [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	1,045,415	1,070,824	1,050,813
Long-Lived assets	135,647	159,362
Americas [Member] | Operating Segments [Member] | United States [Member]
Segment Reporting Information [Line Items]
Revenues	422,584	425,746	388,775
Long-Lived assets	93,941	108,030
Americas [Member] | Operating Segments [Member] | The Philippines [Member]
Segment Reporting Information [Line Items]
Revenues	216,170	205,332	213,132
Long-Lived assets	10,844	14,656
Americas [Member] | Operating Segments [Member] | Canada [Member]
Segment Reporting Information [Line Items]
Revenues	133,549	195,739	210,463
Long-Lived assets	10,278	16,257
Americas [Member] | Operating Segments [Member] | Costa Rica [Member]
Segment Reporting Information [Line Items]
Revenues	114,483	97,295	101,888
Long-Lived assets	7,382	5,625
Americas [Member] | Operating Segments [Member] | El Salvador [Member]
Segment Reporting Information [Line Items]
Revenues	63,462	52,609	46,301
Long-Lived assets	3,329	3,298
Americas [Member] | Operating Segments [Member] | China [Member]
Segment Reporting Information [Line Items]
Revenues	36,270	32,167	25,478
Long-Lived assets	3,523	4,417
Americas [Member] | Operating Segments [Member] | Australia [Member]
Segment Reporting Information [Line Items]
Revenues	23,960	33,126	36,725
Long-Lived assets	2,396	2,923
Americas [Member] | Operating Segments [Member] | Mexico [Member]
Segment Reporting Information [Line Items]
Revenues	18,338	20,439	23,701
Long-Lived assets	1,307	1,575
Americas [Member] | Operating Segments [Member] | Colombia [Member]
Segment Reporting Information [Line Items]
Revenues	7,381	3,073
Long-Lived assets	1,299	1,514
Americas [Member] | Operating Segments [Member] | Brazil [Member]
Segment Reporting Information [Line Items]
Revenues	5,442	3,005	3,288
Long-Lived assets	1,047	844
Americas [Member] | Operating Segments [Member] | India [Member]
Segment Reporting Information [Line Items]
Revenues	3,776	2,293	1,062
Long-Lived assets	301	223
EMEA [Member]
Segment Reporting Information [Line Items]
Goodwill	9,684
EMEA [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues	240,826	256,699	212,647
Long-Lived assets	16,453	11,138
EMEA [Member] | Operating Segments [Member] | Germany [Member]
Segment Reporting Information [Line Items]
Revenues	82,120	88,887	77,950
Long-Lived assets	1,973	2,310
EMEA [Member] | Operating Segments [Member] | Sweden [Member]
Segment Reporting Information [Line Items]
Revenues	56,600	68,057	49,953
Long-Lived assets	1,681	2,478
EMEA [Member] | Operating Segments [Member] | United Kingdom [Member]
Segment Reporting Information [Line Items]
Revenues	50,209	42,328	33,750
Long-Lived assets	3,652	3,871
EMEA [Member] | Operating Segments [Member] | Romania [Member]
Segment Reporting Information [Line Items]
Revenues	15,474	18,288	14,856
Long-Lived assets	678	682
EMEA [Member] | Operating Segments [Member] | Hungary [Member]
Segment Reporting Information [Line Items]
Revenues	9,164	8,723	8,525
Long-Lived assets	536	442
EMEA [Member] | Operating Segments [Member] | Norway [Member]
Segment Reporting Information [Line Items]
Revenues	8,382	10,265	6,768
Long-Lived assets	278	490
EMEA [Member] | Operating Segments [Member] | Finland [Member]
Segment Reporting Information [Line Items]
Revenues	4,643	4,295	4,936
Long-Lived assets	226	92
EMEA [Member] | Operating Segments [Member] | Denmark [Member]
Segment Reporting Information [Line Items]
Revenues	3,898	4,578	4,739
Long-Lived assets	81	95
EMEA [Member] | Operating Segments [Member] | Netherlands [Member]
Segment Reporting Information [Line Items]
Revenues	3,783	3,126	3,073
Long-Lived assets	7,243	9
EMEA [Member] | Operating Segments [Member] | Egypt [Member]
Segment Reporting Information [Line Items]
Revenues	3,552	4,633	4,810
Long-Lived assets	105	172
EMEA [Member] | Operating Segments [Member] | Slovakia [Member]
Segment Reporting Information [Line Items]
Revenues	$ 3,001	3,519	$ 3,287
Long-Lived assets		$ 497