SIGNIFICANT ACCOUNTING POLICIES (Tables)

12 Months Ended

Dec. 31, 2017

Accounting Policies [Abstract]

Schedule of reconciliation of the allowance for doubtful accounts

A reconciliation of the beginning and ending balances of the allowance for doubtful accounts is as follows (in thousands):

	Year Ended December 31,
	2017			2016			2015
Balance, beginning of the period	$	1,059		$	606		$	349
Charges to earnings	195			515			337
Write-off of uncollectible accounts receivable	(579		)	(62		)	(80		)
Balance, end of the period	$	675		$	1,059		$	606

Schedule of depreciation period for each asset category

The following table presents the estimated useful lives for each asset category:

Asset Category	Estimated Useful Lives
Land	N/A
Building	34 years
Site Improvements	1 to 15 years
Computer equipment and capitalized software	1 to 5 years
Leasehold improvements	Lesser of asset life or life of lease
Furniture and other equipment	3 to 7 years
Aircraft and automobile	5 to 10 years