Goodwill and Other Intangible Assets - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill impairment test fair value in excess of carrying amount percentage	30.00%		30.00%
Impairment losses	$ 0
Amortization expense for intangible assets	$ 12,700,000	$ 13,600,000	$ 37,900,000	$ 40,900,000