QUANTA SERVICES INC, QUANTA SERVICES MANAGEMENT ...

QUANTA SERVICES, INC. AND SUBSIDIARIES
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS — (Continued)
7. DETAIL OF CERTAIN BALANCE SHEET ACCOUNTS:
Activity in Quanta’s current and long-term allowance for doubtful accounts consists of the following (in
thousands):
December 31,
2011 2010
Balance at beginning of year ......................................... $7,300 $ 9,069
Charged to expense ................................................. 1,163 (142)
Deductions for uncollectible receivables written off, net of recoveries ......... (4,700) (1,627)
Balance at end of year .............................................. $3,763 $ 7,300
Contracts in progress are as follows (in thousands):
December 31,
2011 2010
Costs incurred on contracts in progress .......................... $2,411,733 $ 3,225,340
Estimated earnings, net of estimated losses ....................... 301,954 580,340
2,713,687 3,805,680
Less — Billings to date ...................................... (2,669,623) (3,753,326)
$ 44,064 $ 52,354
Costs and estimated earnings in excess of billings on uncompleted
contracts ................................................ $ 206,159 $ 135,475
Less — Billings in excess of costs and estimated earnings on
uncompleted contracts ..................................... (162,095) (83,121)
Property and equipment consists of the following (in thousands):
Estimated Useful
Lives in Years
$ 44,064 $ 52,354
December 31,
2011 2010
Land ........................................ N/A $ 16,310 $ 15,698
Buildings and leasehold improvements ............. 5-30 54,365 42,755
Operating equipment and vehicles ................. 5-25 984,585 864,631
Fiber optic and related assets ..................... 5-20 319,303 303,961
Office equipment, furniture and fixtures and
information technology systems ................ 3-15 87,378 71,955
Construction work in progress .................... N/A 29,563 29,793
1,491,504 1,328,793
Less — Accumulated depreciation and amortization . . (519,808) (428,025)
Property and equipment, net ..................... $ 971,696 $ 900,768
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