Income taxes (Tables)
 12 Months Ended
Dec. 31, 2013
Income taxes [Abstract]  
Components of the provision for income taxes attributable to operations
Significant components of the provision for income taxes attributable to operations consist of the following:

 
 
Year ended December 31,
 
(in thousands)
 
2013
  
2012
  
2011
 
Current
 
  
  
 
Federal
 
$
(878
)
 
$
11,481
  
$
11,481
 
State
  
(173
)
  
(1,045
)
  
(1,045
)
International
  
300
   
103
   
103
 
Total current
  
(751
)
  
10,539
   
10,539
 
Deferred
            
Federal
  
12,679
   
3,758
   
3,758
 
State
  
1,028
   
(375
)
  
(375
)
International
  
152
   
-
   
-
 
Total deferred
  
13,859
   
3,383
   
3,383
 
Total provision for income taxes
 
$
13,108
  
$
13,922
  
$
13,922
 
Net deferred tax asset
The Company's net deferred tax asset consists of the following:

 
 
December 31,
 
(in thousands)
 
2013
  
2012
 
Net operating loss carryforward
 
$
23,256
  
$
26,102
 
Research and development carryforward
  
7,395
   
3,556
 
Stock compensation
  
6,378
   
5,289
 
Foreign deferrals
  
64,090
   
64,009
 
Deferred revenue
  
-
   
-
 
Other
  
4,522
   
9,005
 
Deferred tax asset
  
105,641
   
107,961
 
Fixed assets
  
(32,588
)
  
(22,040
)
Other
  
(5,714
)
  
(6,158
)
Deferred tax liability
  
(38,302
)
  
(28,198
)
Valuation allowance
  
(68,846
)
  
(67,412
)
Net deferred tax (liabilities)/assets
 
$
(1,507
)
 
$
12,351
 
Reconciliation of taxes determined by applying U.S. federal statutory rate to loss before provision for income taxes
The provision for income taxes differs from the amount of taxes determined by applying the U.S. federal statutory rate to loss before provision for income taxes as a result of the following:

 
 
Year ended December 31,
 
(in thousands)
 
2013
  
2012
  
2011
 
US
 
$
52,749
  
$
52,391
  
$
66,756
 
International
  
(8,506
)
  
(14,945
)
  
(27,907
)
Earnings before taxes on income
  
44,243
   
37,446
   
38,849
 
 
            
Federal tax at statutory rates
 
$
15,485
  
$
13,106
  
$
13,597
 
State taxes, net of federal benefit
  
538
   
(2,079
)
  
46
 
Impact of foreign operations
  
(1,116
)
  
(3,604
)
  
(2,371
)
Change in valuation allowance
  
1,434
   
4,629
   
3,193
 
Effect of foreign rates
  
-
   
(22
)
  
(12
)
Tax credits
  
(5,918
)
  
(2,904
)
  
(1,405
)
Other differences
  
(227
)
  
139
   
556
 
Permanent differences
  
2,912
   
4,657
   
2,226
 
Provision for income taxes
 
$
13,108
  
$
13,922
  
$
15,830
 
Gross unrecognized tax benefits activity
The table below presents the gross unrecognized tax benefits activity for 2013, 2012 and 2011:

(in thousands)
 
 
Gross unrecognized tax benefits at January 1, 2011
 
$
950
 
Increases for tax positions for prior years
  
167
 
Decreases for tax positions for prior years
  
(61
)
Increases for tax positions for current year
  
-
 
Settlements
  
-
 
Lapse of statute of limitations
  
-
 
Gross unrecognized tax benefits at December 31, 2011
  
1,056
 
Increases for tax positions for prior years
  
25
 
Decreases for tax positions for prior years
  
(65
)
Increases for tax positions for current year
  
-
 
Settlements
  
-
 
Lapse of statute of limitations
  
-
 
Gross unrecognized tax benefits at December 31, 2012
  
1,016
 
Increases for tax positions for prior years
  
165
 
Decreases for tax positions for prior years
  
-
 
Increases for tax positions for current year
  
15
 
Settlements
  
-
 
Lapse of statute of limitations
  
(75
)
Gross unrecognized tax benefits at December 31, 2013
 
$
1,121