8.	DETAIL OF CERTAIN BALANCE SHEET ACCOUNTS:

Activity in Quanta’s current and long-term allowance for doubtful accounts consisted of the following (in thousands):


	December 31,
	2014			2013
Balance at beginning of year	$	5,215		$	5,447
Charged to bad debt expense and provision for long-term contract receivable		103,871			3,236
Deductions for uncollectible receivables written off, net of recoveries		(102,912	)		(3,468	)

Balance at end of year	$	6,174		$	5,215

Included in the 2014 amounts charged and written off was the $102.5 million charge to long-term contract receivable and subsequent write-off related to the Sunrise Powerlink project. See Current and Long-Term Accounts and Notes Receivable and Allowance for Doubtful Accounts in Note 2 for more information.

Contracts in progress were as follows (in thousands):


	December 31,
	2014			2013
Costs incurred on contracts in progress	$	6,603,351		$	6,152,507
Estimated earnings, net of estimated losses		1,111,657			943,090

		7,715,008			7,095,597
Less — Billings to date		(7,675,674	)		(7,121,225	)

	$	39,334		$	(25,628	)

Costs and estimated earnings in excess of billings on uncompleted contracts	$	290,447		$	213,478
Less — Billings in excess of costs and estimated earnings on uncompleted contracts		(251,113	)		(239,106	)

	$	39,334		$	(25,628	)

Property and equipment consisted of the following (in thousands):


	Estimated Useful		December 31,
	Lives in Years		2014			2013
Land		N/A	$	40,657		$	30,743
Buildings and leasehold improvements		5-30		95,058			77,939
Operating equipment and vehicles		5-25		1,460,121			1,199,807
Fiber optic and related assets		5-20		431,690			377,551
Office equipment, furniture and fixtures and information technology systems		3-15		122,914			107,477
Construction work in progress		N/A		69,233			44,030

				2,219,673			1,837,547
Less — Accumulated depreciation and amortization				(739,545	)		(631,939	)

Property and equipment, net			$	1,480,128		$	1,205,608

Accounts payable and accrued expenses consisted of the following (in thousands):


	December 31,
	2014		2013
Accounts payable, trade	$	487,790	$	412,601
Accrued compensation and related expenses		166,331		163,000
Accrued insurance, current portion		49,309		44,608
Current deferred taxes		31,014		16,424
Deferred revenues, current portion		21,309		22,764
Income and franchise taxes payable		20,946		74,499
Other accrued expenses		100,637		68,284

	$	877,336	$	802,180