Capital Lease Obligations
 9 Months Ended
Sep. 30, 2016
Leases, Capital [Abstract]  
Capital Lease Obligations
Capital Lease Obligations
As of September 30, 2016, and December 31, 2015, the Company has approximately $13.7 million of manufacturing equipment acquired under capital leases, included in property and equipment. As of September 30, 2016, one capital lease remains outstanding and is being repaid in equal monthly installments over a 24 month term and includes principal and interest payments with an effective interest rate of 13%.
The assets acquired under capital leases are being amortized on a straight-line basis over five years in accordance with the Company's policy for depreciation of manufacturing equipment. Amortization expense on assets acquired under capital leases is included with depreciation expense. Amortization expense related to these capital leased assets was $0.7 million and $0.6 million in the three months ended September 30, 2016 and 2015, respectively. Amortization expense was $2.1 million and $1.7 million in the nine months ended September 30, 2016 and 2015, respectively.
Assets purchased under capital leases and held consist of the following (in thousands):
 
September 30, 2016
 
December 31, 2015
Manufacturing equipment
$
13,705

 
$
13,705

Less: Accumulated amortization
(6,401
)
 
(4,346
)
    Total
$
7,304

 
$
9,359


The aggregate future minimum lease payments related to the capital lease as of September 30, 2016, are as follows (in thousands):
Years Ending December 31,
Minimum Lease
Payments
2016 (remaining)
$
808

2017
269

Total future minimum lease payments
$
1,077

Interest expense
16

Total capital lease obligations
$
1,061


The Company recorded $0.1 million and $0.3 million of interest expense on capital leases in the three months ended September 30, 2016 and 2015, respectively. The Company recorded $0.3 million and $1.0 million of interest expense on capital leases in the nine months ended September 30, 2016 and 2015, respectively.