Expiration Years of Minimum Alternate Tax Credit (Detail) (Minimum Alternate Tax (MAT), USD $) In Millions, unless otherwise specified	Dec. 31, 2013
Tax Credit Carryforward [Line Items]
Minimum Alternate Tax Credit	$ 20.46
2017-18
Tax Credit Carryforward [Line Items]
Minimum Alternate Tax Credit	0.21
2018-19
Tax Credit Carryforward [Line Items]
Minimum Alternate Tax Credit	0.29
2019-20
Tax Credit Carryforward [Line Items]
Minimum Alternate Tax Credit	1.43
2020-21
Tax Credit Carryforward [Line Items]
Minimum Alternate Tax Credit	5.31
2021-22
Tax Credit Carryforward [Line Items]
Minimum Alternate Tax Credit	0.86
2022-23
Tax Credit Carryforward [Line Items]
Minimum Alternate Tax Credit	6.41
2023-24
Tax Credit Carryforward [Line Items]
Minimum Alternate Tax Credit	$ 5.95