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	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Cash paid during the period for:
Interest	$ 14,899	$ 5,230
Income taxes	8,004	1,532
Significant non-cash investing and financing activities
Other payable issued for purchased customer accounts	5	0
Estimated acquisition earn-out payables and related charges	5,653	280
Notes received on the sale of fixed assets and customer accounts	$ 362	$ 131