Goodwill and Other Intangibles - Schedule of Identifiable Intangibles (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Nonamortizable identifiable intangibles	$ 458,589	$ 488,144
Identifiable intangibles (net of amortization of $153.7 and $131.5 million at December 31, 2016 and 2015, respectively)	201,859	212,161
Total identifiable intangibles	660,448	700,305
Accumulated amortization of identifiable intangibles	$ 153,700	$ 131,500