Quarterly report pursuant to Section 13 or 15(d)

Goodwill and Other Intangible Assets - Other Intangible Assets (Detail)

v3.10.0.1
Goodwill and Other Intangible Assets - Other Intangible Assets (Detail) - USD ($)
$ in Thousands
6 Months Ended
Jun. 30, 2018
Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]    
Intangible Assets $ 611,340 $ 598,686
Accumulated Amortization (352,520) (335,507)
Intangible Assets, Net $ 258,820 263,179
Remaining Weighted Average Amortization Period in Years 8 years 9 months 1 day  
Intangible Assets $ 614,340 598,686
Intangible Assets, Net 261,820 263,179
Engineering license    
Indefinite-lived Intangible Assets [Line Items]    
Intangible Assets 3,000 0
Customer relationships    
Finite-Lived Intangible Assets [Line Items]    
Intangible Assets 326,181 327,334
Accumulated Amortization (150,677) (137,333)
Intangible Assets, Net $ 175,504 190,001
Remaining Weighted Average Amortization Period in Years 6 years 9 months  
Backlog    
Finite-Lived Intangible Assets [Line Items]    
Intangible Assets $ 135,772 136,266
Accumulated Amortization (134,885) (135,847)
Intangible Assets, Net $ 887 419
Remaining Weighted Average Amortization Period in Years 8 months 12 days  
Trade names    
Finite-Lived Intangible Assets [Line Items]    
Intangible Assets $ 80,279 74,797
Accumulated Amortization (19,289) (17,057)
Intangible Assets, Net $ 60,990 57,740
Remaining Weighted Average Amortization Period in Years 15 years 9 months 15 days  
Non-compete agreements    
Finite-Lived Intangible Assets [Line Items]    
Intangible Assets $ 37,601 37,760
Accumulated Amortization (28,843) (27,659)
Intangible Assets, Net $ 8,758 10,101
Remaining Weighted Average Amortization Period in Years 3 years 7 months 1 day  
Patented rights and developed technology    
Finite-Lived Intangible Assets [Line Items]    
Intangible Assets $ 22,507 22,529
Accumulated Amortization (18,427) (17,611)
Intangible Assets, Net $ 4,080 4,918
Remaining Weighted Average Amortization Period in Years 2 years 10 months 20 days  
Curriculum    
Finite-Lived Intangible Assets [Line Items]    
Intangible Assets $ 9,000 0
Accumulated Amortization (399) 0
Intangible Assets, Net $ 8,601 $ 0
Remaining Weighted Average Amortization Period in Years 9 years 7 months