XML 64 R39.htm IDEA: XBRL DOCUMENT v3.8.0.1
Stock Options and Stock-Based Compensation - Weighted Average Assumptions (Detail)
12 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Mar. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Expected volatility 40.00% 41.00% 43.00%
Risk free interest rate, Minimum 1.88% 1.03% 1.25%
Risk free interest rate, Maximum 2.56% 1.92% 1.65%
Dividend yield 0.00% 0.00% 0.00%
Minimum [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Weighted average option life 4 years 4 months 24 days 4 years 4 months 24 days 4 years 4 months 24 days
Maximum [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Weighted average option life 4 years 6 months 4 years 6 months 4 years 6 months