Goodwill and Intangible Assets
 3 Months Ended
May 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]  
Goodwill and Intangible Assets
Goodwill and Intangible Assets
The changes in the carrying amount of goodwill are summarized as follows (in thousands):
Balance as of February 29, 2016
$
69,595

Goodwill acquired
409

Effect of foreign exchange rates
156

Balance as of May 31, 2016
$
70,160


Intangible assets subject to amortization are summarized as follows (in thousands):
 
As of May 31, 2016
 
Gross
Carrying
Amount
 
Accumulated
Amortization
 
Net
Carrying
Value
Acquired developed technology
$
50,133

 
$
(26,849
)
 
$
23,284

Customer relationships
19,862

 
(7,929
)
 
11,933

Patents
2,999

 
(1,417
)
 
1,582

Trade name
812

 
(289
)
 
523

 
$
73,806

 
$
(36,484
)
 
$
37,322

 
As of February 29, 2016
 
Gross
Carrying
Amount
 
Accumulated
Amortization
 
Net
Carrying
Value
Acquired developed technology
$
50,082

 
$
(25,643
)
 
$
24,439

Customer relationships
19,809

 
(7,313
)
 
12,496

Patents
2,999

 
(1,295
)
 
1,704

Trade name
812

 
(259
)
 
553

 
$
73,702

 
$
(34,510
)
 
$
39,192


Certain intangible assets were removed as they were fully amortized as of the periods presented above. In addition to the above, we maintained other intangible assets not subject to amortization of $0.2 million as of May 31, 2016 and February 29, 2016.
Amortization expense, including impairment charges, was $1.9 million and $0.6 million for the three months ended May 31, 2016 and 2015, respectively.
As of May 31, 2016, amortization expense for intangible assets in future periods was as follows: $5.4 million for the remainder of fiscal 2017, $6.9 million for fiscal 2018, $6.0 million for fiscal 2019, $5.8 million for fiscal 2020, $5.3 million for fiscal 2021 and $7.9 million thereafter.