Contracts Receivable and Retainage - Additional Information (Details) $ in Thousands  | 
3 Months Ended | |
|---|---|---|
| 
 Mar. 31, 2016  
USD ($)  
Customer 
 | 
 Dec. 31, 2015  
USD ($) 
 | 
|
| Long-term Contracts or Programs Disclosure [Line Items] | ||
| Contract receivable | $ 45,306 | $ 47,060 | 
| Allowance for bad debt | 97 | |
| Top 4 Customer | ||
| Long-term Contracts or Programs Disclosure [Line Items] | ||
| Contract receivable | $ 23,800 | |
| Percentage of contract receivable | 52.40% | |
| Number of major customers, contracts receivables | Customer | 4 | 
| X | ||||||||||
- Definition Long-term Contracts or Programs Disclosure [Line Items] No definition available. 
  | 
| X | ||||||||||
- Definition Number Of Major Customer, Receivables No definition available. 
  | 
| X | ||||||||||
- Definition Percentage Of Revenue From Major Customer No definition available. 
  | 
| X | ||||||||||
- Definition For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
  | 
| X | ||||||||||
- Definition Amount billed to customers under long-term contracts or programs to be collected in the next fiscal year following the latest fiscal year. Excludes amounts due that have been withheld because of retainage provisions in a contract. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available. 
  | 
| X | ||||||||||
- Details 
  |