Quarterly report pursuant to Section 13 or 15(d)

Stock Incentive Plans - Summary of ESPP Stock Plan Activity (Details)

v2.4.1.9
Stock Incentive Plans - Summary of ESPP Stock Plan Activity (Details) (USD $)
In Thousands, except Share data, unless otherwise specified
 3 Months Ended 0 Months Ended
Mar. 31, 2015
Sep. 01, 2014
Mar. 03, 2014
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Payroll deductions used to purchase shares $ 342us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan    
2014 ESPP Plan      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Employee accumulated payroll deductions   343ingn_AccumulatedPayrollDeductionsValueEmployeeStockPurchasePlan
/ us-gaap_PlanNameAxis
= ingn_TwoThousandAndFourteenEmployeeStockPurchasePlanMember 		414ingn_AccumulatedPayrollDeductionsValueEmployeeStockPurchasePlan
/ us-gaap_PlanNameAxis
= ingn_TwoThousandAndFourteenEmployeeStockPurchasePlanMember
Total shares purchased   18,551us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans
/ us-gaap_PlanNameAxis
= ingn_TwoThousandAndFourteenEmployeeStockPurchasePlanMember 		30,358us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans
/ us-gaap_PlanNameAxis
= ingn_TwoThousandAndFourteenEmployeeStockPurchasePlanMember
Payroll deductions used to purchase shares   342us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan
/ us-gaap_PlanNameAxis
= ingn_TwoThousandAndFourteenEmployeeStockPurchasePlanMember 		413us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan
/ us-gaap_PlanNameAxis
= ingn_TwoThousandAndFourteenEmployeeStockPurchasePlanMember
Transfer to next offering period   $ 1ingn_EmployeeStockPurchasePlanPayrollDeductionsTransferToFutureOfferings
/ us-gaap_PlanNameAxis
= ingn_TwoThousandAndFourteenEmployeeStockPurchasePlanMember 		$ 1ingn_EmployeeStockPurchasePlanPayrollDeductionsTransferToFutureOfferings
/ us-gaap_PlanNameAxis
= ingn_TwoThousandAndFourteenEmployeeStockPurchasePlanMember
FMV at enrollment date per share   $ 21.69ingn_FairMarketValueOfStockPricePerShareEnrollmentDate
/ us-gaap_PlanNameAxis
= ingn_TwoThousandAndFourteenEmployeeStockPurchasePlanMember 		$ 16.00ingn_FairMarketValueOfStockPricePerShareEnrollmentDate
/ us-gaap_PlanNameAxis
= ingn_TwoThousandAndFourteenEmployeeStockPurchasePlanMember
FMV at purchase date per share   $ 33.62ingn_FairMarketValueOfStockPricePerSharePurchaseDate
/ us-gaap_PlanNameAxis
= ingn_TwoThousandAndFourteenEmployeeStockPurchasePlanMember 		$ 21.69ingn_FairMarketValueOfStockPricePerSharePurchaseDate
/ us-gaap_PlanNameAxis
= ingn_TwoThousandAndFourteenEmployeeStockPurchasePlanMember
Purchase price per share   $ 18.44ingn_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerSharePriceOfSharesPurchased
/ us-gaap_PlanNameAxis
= ingn_TwoThousandAndFourteenEmployeeStockPurchasePlanMember 		$ 13.60ingn_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerSharePriceOfSharesPurchased
/ us-gaap_PlanNameAxis
= ingn_TwoThousandAndFourteenEmployeeStockPurchasePlanMember