Acquired Intangible Assets, net

The Company evaluates the recoverability of its long-lived assets for impairment when indicators of potential impairment arise. The Company did not recognize any impairment of its acquired intangible assets during fiscal year 2017, 2016 or 2015.

Acquired intangible assets, net, as of April 30, 2017 and April 30, 2016 for continuing operations are as follows (in thousands):



	April 30, 2017							April 30, 2016
	Gross Fair Value		Accumulated Amortization			Net Book Value		Gross Fair Value		Accumulated Amortization			Net Book Value
Customer relationships	$	11,835	$	(5,395	)	$	6,440	$	11,835	$	(4,158	)	$	7,677
Developed technology	3,265		(1,988		)	1,277		3,265		(1,335		)	1,930
Total	$	15,100	$	(7,383	)	$	7,717	$	15,100	$	(5,493	)	$	9,607

The amortization of customer relationships is recorded as amortization expense and the amortization for developed technology is recorded in cost of revenue. For the years ended April 30, 2017, 2016 and 2015, the Company incurred amortization expense of acquired intangible assets of $1.9 million, $1.9 million and $1.9 million, respectively.

The following table presents our estimate of future amortization expense for definite-lived intangible assets (in thousands):



Fiscal period:	Amount
2018	$	1,890
2019	1,856
2020	1,130
2021	1,130
2022	1,130
Thereafter	581
Total	$	7,717