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Acquired Intangible Assets, net for Continuing Operations (Details) - USD ($) $ in Thousands | Jan. 31, 2016 | Apr. 30, 2015
--- | --- | ---
Acquired Finite Lived and Indefinite Lived Intangible Assets [Line Items] |  |
Gross Fair Value | $ 15,100 | $ 15,100
Accumulated Amortization | (5,020) | (3,602)
Total | 10,080 | 11,498
Customer relationships |  |
Acquired Finite Lived and Indefinite Lived Intangible Assets [Line Items] |  |
Acquired finite-lived intangible assets, gross | 11,835 | 11,835
Accumulated Amortization | (3,849) | (2,921)
Acquired finite-lived intangible assets, net book value | 7,986 | 8,914
Developed technology |  |
Acquired Finite Lived and Indefinite Lived Intangible Assets [Line Items] |  |
Acquired finite-lived intangible assets, gross | 3,265 | 3,265
Accumulated Amortization | (1,171) | (681)
Acquired finite-lived intangible assets, net book value | $ 2,094 | $ 2,584

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