RECEIVABLES (Tables)

12 Months Ended

May. 31, 2015

Summary of Accounts Receivable

A summary of accounts receivable as of May 31, 2015 and 2014 is as follows (in thousands):

	May 31,
	2015			2014
Trade accounts receivable	$	197,322		$	165,484
Unbilled revenues		18,387			14,901
Allowance for doubtful accounts		(2,775	)		(4,784	)
Total	$	212,934		$	175,601

Summary of Activity in Allowance for Doubtful Accounts

The following summarizes the activity in the allowance for doubtful accounts as of May 31, 2015, 2014 and 2013 (in thousands):

	Twelve Months Ended May 31,
	2015			2014			2013
Balance at beginning of year	$	4,784		$	5,438		$	4,405
Provision for doubtful accounts		233			2,140			2,922
Write-off of bad debts		(2,242	)		(2,794	)		(1,889	)
Balance at end of year	$	2,775		$	4,784		$	5,438