Revenue - Contract Balances and Refund Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Apr. 02, 2018	Apr. 01, 2018
Revenue from Contract with Customer [Abstract]
Contract assets - unbilled revenue	$ 751	$ 1,595
Refund liabilities - price adjustment and other revenue reserves	(11,448)	(10,964)	$ 0
Contract Liabilities - short-term	(774)	(778)
Contract Liabilities - long-term	$ (967)	$ (1,354)

Amount, before allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

+ References

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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of liability for consideration received or receivable from customer which is not included in transaction price, when consideration is expected to be refunded to customer.

+ References

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-URI http://asc.fasb.org/extlink&oid=108792157&loc=SL49130611-203046-203046

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- References

No definition available.

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