Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Current Assets:
Cash and cash equivalents	$ 117,366	$ 128,771
Accounts receivable, net of allowances of $2,757 and $5,226	1,565,080	1,621,133
Costs and estimated earnings in excess of billings on uncompleted contracts	497,846	317,745
Inventories	89,109	75,285
Prepaid expenses and other current assets	135,950	134,585
Total current assets	2,405,351	2,277,519
Property and equipment, net of accumulated depreciation of $852,073 and $755,272	1,165,687	1,101,959
Other assets, net	95,636	76,333
Other intangible assets, net of accumulated amortization of $291,461 and $264,674	197,556	205,074
Goodwill	1,612,238	1,552,658
Total assets	5,476,468	5,213,543
Current Liabilities:
Current maturities of long-term debt and short-term borrowings	5,061	7,067
Accounts payable and accrued expenses	928,487	782,134
Billings in excess of costs and estimated earnings on uncompleted contracts	310,993	399,230
Current liabilities of discontinued operations	1,367	15,313
Total current liabilities	1,245,908	1,203,744
Long-term debt and notes payable, net of current maturities	482,399	475,364
Deferred income taxes	184,341	186,491
Insurance and other non-current liabilities	287,235	260,129
Total liabilities	2,199,883	2,125,728
Commitments and Contingencies
Equity:
Common stock, value	2	2
Additional paid-in capital	3,689,171	3,497,740
Retained earnings	1,788,498	1,677,698
Accumulated other comprehensive loss	(242,825)	(294,689)
Treasury stock, 84,766,994 and 74,991,343 common shares, at cost	(1,960,910)	(1,795,257)
Total stockholders' equity	3,273,936	3,085,494
Non-controlling interests	2,649	2,321
Total equity	3,276,585	3,087,815
Total liabilities and equity	5,476,468	$ 5,213,543
Exchangeable Shares [Member]
Equity:
Common stock, value
Series F Preferred Stock [Member]
Equity:
Preferred Stock, value
Series G Preferred Stock [Member]
Equity:
Preferred Stock, value

Sum of the carrying values as of the balance sheet date of obligations incurred through that date and due within one year (or the operating cycle, if longer), including liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received, taxes, interest, rent and utilities, accrued salaries and bonuses, payroll taxes and fringe benefits.

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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.