Quarterly report pursuant to Section 13 or 15(d)

Acquisition of Citizen Engagement Centers Business - Narrative (Details)

v3.19.1
Acquisition of Citizen Engagement Centers Business - Narrative (Details) - USD ($)
3 Months Ended 6 Months Ended 12 Months Ended
Nov. 16, 2018
Mar. 31, 2019
Dec. 31, 2018
Mar. 31, 2019
Mar. 31, 2018
Sep. 30, 2018
Business Acquisition [Line Items]            
Cash payment to acquire business       $ 421,809,000 $ 157,000  
Payments to acquire software licenses       18,541,000 $ 13,175,000  
Goodwill   $ 587,751,000   587,751,000   $ 399,882,000
Goodwill, impairment loss       0    
General Dynamics Information Technology's Citizen Engagement Centers            
Business Acquisition [Line Items]            
Cash payment to acquire business $ 400,000,000.0          
Estimated cash consideration   430,573,000 $ 429,335,000      
Business combination, acquisition related costs       2,700,000   $ 500,000
Payments to acquire software licenses       4,500,000    
Goodwill 188,100,000 188,062,000 187,877,000 188,062,000    
Intangible assets 122,300,000 $ 122,300,000 $ 122,300,000 $ 122,300,000    
Average weighted intangible assets useful life (years)       7 years 7 months 6 days    
General Dynamics Information Technology's Citizen Engagement Centers | Line of Credit            
Business Acquisition [Line Items]            
Proceeds from long-term lines of credit $ 150,000,000          
Weighted Average            
Business Acquisition [Line Items]            
Useful life       9 years 2 months 12 days    
Customer contracts and relationships | Weighted Average            
Business Acquisition [Line Items]            
Useful life       9 years 2 months 12 days    
Technology-based Rights | Weighted Average            
Business Acquisition [Line Items]            
Useful life       4 years 7 months 6 days    
Trademarks and trade names | Weighted Average            
Business Acquisition [Line Items]            
Useful life       9 months 18 days    
Customer relationships - all contracts except U.S. Census | General Dynamics Information Technology's Citizen Engagement Centers            
Business Acquisition [Line Items]            
Useful life       10 years    
Customer relationships - U.S. Census | General Dynamics Information Technology's Citizen Engagement Centers            
Business Acquisition [Line Items]            
Useful life       2 years