Supplemental Cash Flow Information - Supplemental Information About Cash Flows (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION:
Cash paid during the period for interest	$ 121,998	$ 113,690
Cash paid during the period for income taxes, net of refunds of $4,811 and $3,841	39,195	89,635
SUPPLEMENTAL DISCLOSURE OF NONCASH INVESTING ACTIVITIES:
Accrued obligations for the purchase of property and equipment	3,863	12,380
SUPPLEMENTAL DISCLOSURE OF NONCASH FINANCING ACTIVITIES:
Accrued dividends	$ 1,327	$ 1,040