Carrying Amount of Goodwill (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Goodwill [Line Items]
Balance as of beginning of period	$ 2,016,169
Goodwill		$ 2,394,825
Currency translation and other	(1,619)
Accumulated impairment losses		(378,656)
Balance as of end of period	2,014,550
Goodwill	2,014,550	2,016,169
CPE
Goodwill [Line Items]
Balance as of beginning of period	1,391,171
Goodwill		1,391,171
Currency translation and other	(1,619)
Balance as of end of period	1,389,552
Goodwill	1,389,552	1,391,171
N & C
Goodwill [Line Items]
Balance as of beginning of period	624,998
Goodwill		1,003,654
Accumulated impairment losses		(378,656)
Balance as of end of period	624,998
Goodwill	$ 624,998	$ 624,998