Supplemental Cash Flow Information (Tables)

6 Months Ended

Jun. 30, 2016

Supplemental Cash Flow Information [Abstract]

Supplemental Disclosure of Cash Flow Information and Non-cash Investing and Financing Activities

	Six Months Ended June 30,
	2016			2015
Supplemental disclosure of cash flow information:
Interest paid	$	217,783		$	244,977
Income taxes paid	10,186			8,489
Supplemental disclosure of non-cash investing and financing activities:
Increase (decrease) in accounts payable for purchases of property and equipment	(10,197		)	(10,102		)
Purchase of property and equipment under capital leases and installment purchases	25,444			25,769
Installment payment receivable for sale of CCAL (see note 3)	—			117,384