4.	DETAILS OF SELECTED BALANCE SHEET ACCOUNTS

Additional information regarding selected balance sheet accounts at

September 30, 2017

and

December 31, 2016

is presented below (in thousands):

	September 30, 2017			December 31, 201 6
Accounts receivable, net:
Trade	$	40,790		$	39,442
Unbilled revenue		21,659			16,063
Other		1,309			1,435
Total accounts receivable		63,758			56,940
Allowance for doubtful accounts		(645	)		(638	)
Total accounts receivable, net	$	63,113		$	56,302

	September 30, 2017		December 31, 201 6
Inventories:
Finished goods and purchased products	$	2,371	$	1,700
Work in process		882		3
Raw materials		1,604		1,409
Total inventories	$	4,857	$	3,112

During the

third

quarter of

2016,

we recorded a

$0.9

million write-down of inventory at our modular construction and manufacturing plant in Canada, which is included in

Service and other costs in our accompanying unaudited consolidated statements of operations.

	Estimated Useful Life (in years)			September 30, 2017			December 31, 201 6
Property, plant and equipment, net:
Land				$	42,563		$	41,122
Accommodations assets	3	-	15		1,665,496			1,554,986
Buildings and leasehold improvements	5	-	20		31,015			28,104
Machinery and equipment	4	-	15		10,242			9,667
Office furniture and equipment	3	-	7		54,770			29,948
Vehicles	3	-	5		15,319			14,725
Construction in progress					3,163			23,016
Total property, plant and equipment					1,822,568			1,701,568
Accumulated depreciation					(1,066,430	)		(911,858	)
Total property, plant and equipment, net				$	756,138		$	789,710

	September 30, 2017		December 31, 201 6
Accrued liabilities:
Accrued compensation	$	16,270	$	13,189
Accrued taxes, other than income taxes		1,568		917
Accrued interest		15		194
Other		1,576		522
Total accrued liabilities	$	19,429	$	14,822