Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements (Details)

v2.4.1.9
Fair Value Measurements (Details) (USD $)
In Thousands, unless otherwise specified
3 Months Ended
Mar. 31, 2015
Dec. 31, 2014
WMS    
Fair Value Measurements    
The cash flow period from the acquisition date used in determining fair value 3 years  
Klein Decisions, Inc.    
Fair Value Measurements    
The cash flow period from the acquisition date used in determining fair value 3 years  
Level 1 | Recurring Basis | Money market funds    
Fair Value Measurements    
Cash and cash equivalents 52,721us-gaap_CashAndCashEquivalentsFairValueDisclosure
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$ 70,760us-gaap_CashAndCashEquivalentsFairValueDisclosure
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