Supplemental Disclosures of Cash Flow Information and Non-Cash Financing and Investing Activities - Significant Non-Cash Investing and Financing Activities (Detail) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
Supplemental Cash Flow Elements [Abstract]
Interest	$ 11,070	$ 7,660
Income taxes	58,079	52,077
Other payable issued for purchased customer accounts	125	257
Estimated acquisition earn-out payables and related charges	13,158	1,833
Notes received on the sale of fixed assets and customer accounts	$ 131	$ 614