Description of Business and Summary of Significant Accounting Policies - Summary of Cumulative Catch-Up Adjustments (Details) - Contracts accounted for under percentage of completion - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Concentration Risk [Line Items] | |||
| Favorable adjustments | $ 15,296 | $ 9,721 | $ 3,981 |
| Unfavorable adjustments | (7,837) | (11,641) | (6,629) |
| Net favorable (unfavorable) adjustments | $ 7,459 | $ (1,920) | (2,648) |
| Tethered Aerostat Radar System | |||
| Concentration Risk [Line Items] | |||
| Unfavorable adjustments | $ (2,500) | ||