Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies (Details 3)

v2.4.1.9
Summary of Significant Accounting Policies (Details 3) (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Mar. 31, 2013
Revenue by product      
Total $ 115,461us-gaap_Revenues $ 133,105us-gaap_Revenues $ 127,557us-gaap_Revenues
C30      
Revenue by product      
Total 4,804us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_C30Member
5,623us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_C30Member
6,756us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_C30Member
C65      
Revenue by product      
Total 30,118us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_C65Member
29,107us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_C65Member
22,899us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_C65Member
TA100      
Revenue by product      
Total 318us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_TA100Member
460us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_TA100Member
1,485us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_TA100Member
C200      
Revenue by product      
Total 7,120us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_C200Member
14,754us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_C200Member
18,099us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_C200Member
C600      
Revenue by product      
Total 5,848us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_C600Member
10,374us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_C600Member
12,384us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_C600Member
C800      
Revenue by product      
Total 8,319us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_C800Member
10,127us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_C800Member
5,324us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_C800Member
C1000      
Revenue by product      
Total 32,685us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_C1000Member
38,141us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_C1000Member
35,571us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_C1000Member
Waste heat recovery generator      
Revenue by product      
Total 155us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_WasteHeatRecoveryGeneratorMember
180us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_WasteHeatRecoveryGeneratorMember
 
Unit upgrades      
Revenue by product      
Total     129us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_UnitUpgradesMember
Total from Micro turbine Products      
Revenue by product      
Total 89,367us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_MicroTurbineProductsMember
108,766us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_MicroTurbineProductsMember
102,647us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_MicroTurbineProductsMember
Accessories, Parts and Service      
Revenue by product      
Total $ 26,094us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_AccessoriesPartsAndServiceMember
$ 24,339us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_AccessoriesPartsAndServiceMember
$ 24,910us-gaap_Revenues
/ us-gaap_ProductOrServiceAxis
= cpst_AccessoriesPartsAndServiceMember