Annual report pursuant to Section 13 and 15(d)

Fair Value Measurements (Details)

v2.4.1.9
Fair Value Measurements (Details) (USD $)
In Thousands, unless otherwise specified
 12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
WMS    
Fair Value Measurements    
The cash flow period from the acquisition date used in determining fair value 3 years  
Klein Decisions, Inc.    
Fair Value Measurements    
The cash flow period from the acquisition date used in determining fair value 3 years  
Level 1 | Recurring Basis | Money market funds    
Fair Value Measurements    
Cash and cash equivalents 70,760us-gaap_CashAndCashEquivalentsFairValueDisclosure
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= us-gaap_FairValueMeasurementsRecurringMember 		$ 32,358us-gaap_CashAndCashEquivalentsFairValueDisclosure
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