Restructuring (Details) (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Dec. 31, 2013
Employee
Restructuring Cost and Reserve [Line Items]  
Headcount reduction 14
Total incurred $ 2,806
Summary of activity for liabilities [Roll Forward]  
Beginning balance 0
Expenses incurred 2,679
Amount paid (2,225)
Other adjustments 0
Ending balance 454
Restructuring expenses 2,679
EPDU Restructuring Plan [Member]
 
Summary of activity for liabilities [Roll Forward]  
Beginning balance 0
Amount paid (134)
Other adjustments 0
Ending balance 0
Termination benefits [Member]
 
Restructuring Cost and Reserve [Line Items]  
Total incurred 2,114
Termination benefits [Member] | EPDU Restructuring Plan [Member]
 
Summary of activity for liabilities [Roll Forward]  
Beginning balance 0
Expenses incurred 2,114
Amount paid (1,660)
Other adjustments 0
Ending balance 454
Restructuring expenses 2,114
Contract termination costs [Member]
 
Restructuring Cost and Reserve [Line Items]  
Total incurred 431
Contract termination costs [Member] | EPDU Restructuring Plan [Member]
 
Summary of activity for liabilities [Roll Forward]  
Beginning balance 0
Expenses incurred 431
Amount paid (431)
Other adjustments 0
Ending balance 0
Restructuring expenses 431
Other costs [Member]
 
Restructuring Cost and Reserve [Line Items]  
Total incurred 261
Other costs [Member] | EPDU Restructuring Plan [Member]
 
Summary of activity for liabilities [Roll Forward]  
Expenses incurred 134
Restructuring expenses $ 134