Goodwill and Other Intangible Assets (Narrative) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Goodwill and Other Intangible Assets [Line Items]
Amortization expense of intangible assets	$ 2.2	$ 2.1
Customer relationships
Goodwill and Other Intangible Assets [Line Items]
Amortization period of intangible assets, in years	15 years
Non-compete agreements
Goodwill and Other Intangible Assets [Line Items]
Amortization period of intangible assets, in years	5 years
Other intangible assets
Goodwill and Other Intangible Assets [Line Items]
Amortization period of intangible assets, in years	15 years