Description of Business and Summary of Significant Accounting Policies - Additional Information (Detail) | 1 Months Ended | 12 Months Ended | 97 Months Ended | |
Dec. 31, 2014USD ($)$ / sharesshares | Mar. 31, 2016USD ($)CustomerSegment | Mar. 31, 2015USD ($)Customer | Mar. 31, 2014USD ($)Customer | Mar. 31, 2016USD ($) | Apr. 30, 2014$ / sharesshares |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] | | | | | | |
Company incorporation date | | Feb. 20, 2008 | | | | |
Entity Incorporation, State Name | | Delaware | | | | |
Proceeds from sale of common stock, net of underwriters' discounts and commissions | | | $ 119,924,000 | | | |
Number of reportable segments | Segment | | 1 | | | | |
Cash and cash equivalents, original maturity term | | Three months or less | | | | |
Other-than-temporarily impaired investments | | $ 0 | 0 | | | |
Gross value of capitalized internal use software | | 7,700,000 | 10,000,000 | $ 5,500,000 | $ 7,700,000 | |
Stock-based compensation costs | | 1,000,000 | 1,000,000 | 300,000 | | |
Amortization expense | | 6,700,000 | 3,900,000 | 2,100,000 | | |
Net book value of capitalized software | | 12,600,000 | 12,600,000 | | 12,600,000 | |
Impairment of long-lived assets | | $ 0 | 0 | $ 0 | | |
Goodwill impairment | | | | | 0 | |
Current deferred tax liabilities | | | $ 913,000 | | | |
Minimum [Member] | | | | | | |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] | | | | | | |
Revenue recognition, contract term | | 1 month | | | | |
Maximum [Member] | | | | | | |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] | | | | | | |
Revenue recognition, contract term | | 12 months | | | | |
Computers and software [Member] | | | | | | |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] | | | | | | |
Property plant and equipment estimated useful life | | 3 years | | | | |
Other Office Equipment and Site-related Computer Hardware [Member] | | | | | | |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] | | | | | | |
Property plant and equipment estimated useful life | | 3 years | | | | |
Furniture and Fixtures [Member] | | | | | | |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] | | | | | | |
Property plant and equipment estimated useful life | | 5 years | | | | |
Leasehold Improvements [Member] | | | | | | |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] | | | | | | |
Property plant and equipment, estimated useful life | | The shorter of the lease-term or the estimated useful life of the related asset. | | | | |
Capitalized Software Development Costs [Member] | | | | | | |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] | | | | | | |
Property plant and equipment estimated useful life | | 3 years | | | | |
Common Stock [Member] | | | | | | |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] | | | | | | |
Number of common stock shares issued upon conversion of convertible preferred stock | shares | 24,885,778 | | | | | |
Accounts Receivable [Member] | | | | | | |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] | | | | | | |
Number of customers | Customer | | 0 | 1 | | | |
Revenue [Member] | | | | | | |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] | | | | | | |
Number of customers | Customer | | 0 | 0 | 0 | | |
Series F Convertible Preferred Stock [Member] | | | | | | |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] | | | | | | |
Common stock shares issued, price per share | $ / shares | | | | | | $ 28.93 |
Convertible preferred stock conversion rate | shares | 1.02 | | | | | 1 |
Series A Through E Preferred Stock [Member] | | | | | | |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] | | | | | | |
Convertible preferred stock conversion rate | shares | 1 | | | | | |
Convertible Preferred Stock [Member] | | | | | | |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] | | | | | | |
Number of convertible preferred stock shares converted | shares | 24,813,343 | | | | | |
Credit Concentration Risk [Member] | Accounts Receivable [Member] | | | | | | |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] | | | | | | |
Concentration of risk, percentage | | 10.00% | 12.00% | | | |
Credit Concentration Risk [Member] | Revenue [Member] | | | | | | |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] | | | | | | |
Concentration of risk, percentage | | 10.00% | 10.00% | 10.00% | | |
Initial Public Offering [Member] | | | | | | |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] | | | | | | |
Common stock shares issued | shares | 5,750,000 | | | | | |
Proceeds from sale of common stock, net of underwriters' discounts and commissions | $ 123,000,000 | | | | | |
Common stock shares issued, price per share | $ / shares | $ 23 | | | | | $ 23 |
Offering expenses | $ 3,100,000 | | | | | |
Initial Public Offering [Member] | Series F Convertible Preferred Stock [Member] | | | | | | |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] | | | | | | |
Convertible preferred stock conversion rate | shares | | | | | | 11.02 |
Sales and Marketing [Member] | | | | | | |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] | | | | | | |
Advertising Expense | | $ 25,500,000 | $ 25,100,000 | $ 22,400,000 | | |
Restatement Adjustment [Member] | New Accounting Pronouncement, Early Adoption, Effect [Member] | | | | | | |
Description Of Business And Summary Of Significant Accounting Policies [Line Items] | | | | | | |
Current deferred tax liabilities | | (900,000) | | | (900,000) | |
Non-current deferred tax liabilities | | $ 900,000 | | | $ 900,000 | |