Commitments and Contingencies - Additional Information (Details) $ in Thousands					3 Months Ended								12 Months Ended
	Dec. 14, 2015	Nov. 21, 2014 USD ($)	Nov. 13, 2014 USD ($) ft² Term	Jun. 04, 2014 USD ($)	Apr. 30, 2017 USD ($)	Jan. 31, 2017 USD ($)	Oct. 31, 2016 USD ($)	Jul. 31, 2016 USD ($)	Apr. 30, 2016 USD ($)	Jan. 31, 2016 USD ($)	Oct. 31, 2015 USD ($)	Jul. 31, 2015 USD ($)	Apr. 30, 2017 USD ($)	Apr. 30, 2016 USD ($)	Apr. 30, 2015 USD ($)
Operating Leased Assets [Line Items]
Office space | ft²			137,615
Lease commencement date	Dec. 14, 2015
Number of successive periods of five years terms | Term			2
Lease extension period			5 years
Operating leases, rent expense													$ 4,900	$ 5,000	$ 4,100
Operating leases, future minimum payments due, future minimum sublease rentals					$ 2,700								2,700
Loss Contingency, Accrual, Noncurrent					500								500
Revolving line of credit					0				$ 42,000				0	42,000
Sales Tax Refund					3,341	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	3,341	0	0
Cash consideration				$ 30,000											30,000
Amount that placed into escrow as partial security for the Company's indemnification obligations				$ 4,500
Discontinued operation, loss on disposal of discontinued operation, net of tax previously recognized															(10,729)
Loss on disposal of discontinued operations, net of tax													0	$ 0	$ (1,537)
Office space lease contract
Operating Leased Assets [Line Items]
Security deposit for the lease			$ 8,000
Revolving credit facility
Operating Leased Assets [Line Items]
Repayments of debt					10,000
Revolving line of credit					$ 32,000								$ 32,000
Credit facility | Revolving credit facility
Operating Leased Assets [Line Items]
Line of Credit Facility, maximum borrowing capacity		$ 70,000
Revolving letter of credit with a borrowing capacity		15,000
Line of Credit Facility, expiration date													Nov. 21, 2017
Swingline Loan | Credit facility | Revolving credit facility
Operating Leased Assets [Line Items]
Line of Credit Facility, maximum borrowing capacity		$ 3,000
Daily adjusting LIBOR rate | Credit facility | Revolving credit facility
Operating Leased Assets [Line Items]
Interest above daily adjusting LIBOR rate		3.50%