Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
CURRENT ASSETS:
Cash and cash equivalents	$ 26,366	$ 35,941
Accounts receivable, net	366,121	382,458
Materials and supplies	47,626	45,790
Prepaid expenses and other	47,018	43,197
Total current assets	487,131	507,386
PROPERTY AND EQUIPMENT, net	4,209,583	4,215,063
GOODWILL	824,957	826,575
INTANGIBLE ASSETS, net	1,053,664	1,128,952
DEFERRED INCOME TAX ASSETS, net	2,623	2,270
OTHER ASSETS, net	37,928	22,836
Total assets	6,615,886	6,703,082
CURRENT LIABILITIES:
Current portion of long-term debt	85,841	75,966
Accounts payable	246,171	282,275
Accrued expenses	163,893	169,586
Total current liabilities	495,905	527,827
LONG-TERM DEBT, less current portion	1,977,649	2,205,785
DEFERRED INCOME TAX LIABILITIES, net	994,670	983,136
DEFERRED ITEMS - grants from outside parties	302,223	292,198
OTHER LONG-TERM LIABILITIES	185,749	174,675
COMMITMENTS AND CONTINGENCIES
EQUITY:
Additional paid-in capital	1,376,805	1,355,345
Retained earnings	1,676,879	1,544,676
Accumulated other comprehensive loss	(163,831)	(153,457)
Treasury stock, at cost	(230,872)	(227,808)
Total equity	2,659,690	2,519,461
Total liabilities and equity	6,615,886	6,703,082
Class A Common Stock, $0.01 par value, one vote per share; 180,000,000 shares authorized at September 30, 2016 and December 31, 2015; 70,071,227 and 69,674,185 shares issued and 57,290,856 and 56,945,384 shares outstanding (net of 12,780,371 and 12,728,801 shares in treasury) on September 30, 2016 and December 31, 2015, respectively
EQUITY:
Common Stock	701	697
Class B Common Stock, $0.01 par value, ten votes per share; 30,000,000 shares authorized at September 30, 2016 and December 31, 2015; 793,138 shares issued and outstanding on September 30, 2016 and December 31, 2015
EQUITY:
Common Stock	$ 8	$ 8

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Balance Type:	credit
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- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.