Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Current Assets:
Cash and cash equivalents	$ 101,736	$ 138,285
Accounts receivable, net of allowances of $5,090 and $4,465	2,088,682	1,985,077
Contract assets	498,190	497,292
Inventories	94,548	80,890
Prepaid expenses and other current assets	173,913	168,363
Total current assets	2,957,069	2,869,907
Property and equipment, net of accumulated depreciation of $1,011,535 and $981,275	1,301,545	1,288,602
Other assets, net	221,091	189,866
Other intangible assets, net of accumulated amortization of $343,862 and $335,507	270,826	263,179
Goodwill	1,902,871	1,868,600
Total assets	6,653,402	6,480,154
Current Liabilities:
Current maturities of long-term debt	2,775	1,220
Accounts payable and accrued expenses	1,040,661	1,057,460
Contract liabilities	506,203	433,387
Total current liabilities	1,549,639	1,492,067
Long-term debt and notes payable, net of current maturities	882,795	670,721
Deferred income taxes	196,892	179,381
Insurance and other non-current liabilities	377,111	342,356
Total liabilities	3,006,437	2,684,525
Commitments and Contingencies
Equity:
Common stock, value	2	2
Additional paid-in capital	1,920,897	1,889,356
Retained earnings	2,226,916	2,191,059
Accumulated other comprehensive loss	(228,409)	(203,395)
Treasury stock, 7,228,364 and 1,876,828 common shares	(276,054)	(85,451)
Total stockholders’ equity	3,643,352	3,791,571
Non-controlling interests	3,613	4,058
Total equity	3,646,965	3,795,629
Total liabilities and equity	6,653,402	6,480,154
Exchangeable Shares
Equity:
Common stock, value	0	0
Series G Preferred Stock
Equity:
Preferred Stock, value	$ 0	$ 0

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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Balance Type:	credit
Period Type:	instant

- 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.