Discontinued Operations - Held for Sale Operations and Asset Disposals - Schedule of Major Classes of Revenue And Income (Losses) With Respect to the Discontinued Operations (Detail) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Assets with respect to discontinued operations        
Cash and cash equivalents $ 0 $ 708 $ 1,514 $ 6,226
Total liabilities associated with discontinued operations 4,027 67,876    
Discontinued Operations, Disposed of by Sale        
Revenues from External Customers and Long-Lived Assets [Line Items]        
Contract revenue 231,560 468,436 605,382  
Contract costs 198,731 403,969 530,397  
Amortization of intangibles 793 3,138 8,327  
(Gain) Loss on sale of subsidiaries (152,208) 8,161 (20,984)  
General and administrative 26,567 51,530 48,744  
Other charges 4,405 305    
Operating income (loss) 153,272 1,333 38,898  
Non-operating income (expense) (30) (208) 459  
Pre-tax income (loss) 153,242 1,125 39,357  
Provision for income taxes 57,210 6,344 18,526  
Net income (loss) 96,032 (5,219) 20,831  
Assets with respect to discontinued operations        
Cash and cash equivalents   708    
Accounts receivable, net 322 86,140    
Contract cost and recognized income not yet billed 924 9,185    
Prepaid expenses and other current assets 1 6,180    
Parts and supplies inventories   2,477    
Property, plant and equipment, net   9,294    
Intangible assets, net   18,860    
Other   11,997    
Total assets 1,247 144,841    
Accounts payable and accrued liabilities 1,267 42,088    
Contract billings in excess of costs 1,457 1,824    
Current and long-term debt 1,303 17,646    
Other current and long-term liabilities 1,423 6,318    
Total liabilities associated with discontinued operations 5,450 67,876    
Net liabilities associated with discontinued operations (4,203) 76,965    
Discontinued Operations, Disposed of by Sale | Oman        
Revenues from External Customers and Long-Lived Assets [Line Items]        
Contract revenue 0 0 0  
Contract costs 0 0 0  
Amortization of intangibles 0 0 0  
(Gain) Loss on sale of subsidiaries 0 0 (23,639)  
General and administrative 0 0 0  
Other charges 0 0    
Operating income (loss) 0 0 23,639  
Non-operating income (expense) 0 0 0  
Pre-tax income (loss) 0 0 23,639  
Provision for income taxes 0 0 0  
Net income (loss) 0 0 23,639  
Discontinued Operations, Disposed of by Sale | Professional Services Segment        
Revenues from External Customers and Long-Lived Assets [Line Items]        
Contract revenue 229,482 432,379 395,875  
Contract costs 197,414 355,109 323,434  
Amortization of intangibles 793 2,486 2,566  
(Gain) Loss on sale of subsidiaries (152,208) 0 0  
General and administrative 26,937 48,840 41,180  
Other charges 4,405 305    
Operating income (loss) 152,141 25,639 28,695  
Non-operating income (expense) (36) 35 (5)  
Pre-tax income (loss) 152,105 25,674 28,690  
Provision for income taxes 57,210 6,344 18,526  
Net income (loss) 94,895 19,330 10,164  
Assets with respect to discontinued operations        
Cash and cash equivalents   708    
Accounts receivable, net 313 80,576    
Contract cost and recognized income not yet billed 924 9,119    
Prepaid expenses and other current assets 0 6,164    
Parts and supplies inventories   2,477    
Property, plant and equipment, net   8,783    
Intangible assets, net   18,860    
Other   11,097    
Total assets 1,237 137,784    
Accounts payable and accrued liabilities 815 38,118    
Contract billings in excess of costs 1,457 1,824    
Current and long-term debt 1,303 17,646    
Other current and long-term liabilities 1,423 5,103    
Total liabilities associated with discontinued operations 4,998 62,691    
Net liabilities associated with discontinued operations (3,761) 75,093    
Discontinued Operations, Disposed of by Sale | CTS        
Revenues from External Customers and Long-Lived Assets [Line Items]        
Contract revenue 0 24,361 127,783  
Contract costs 0 24,132 118,422  
Amortization of intangibles 0 652 2,609  
(Gain) Loss on sale of subsidiaries 0 8,161 0  
General and administrative 0 954 4,152  
Other charges 0 0    
Operating income (loss) 0 (9,538) 2,600  
Non-operating income (expense) 0 0 498  
Pre-tax income (loss) 0 (9,538) 3,098  
Provision for income taxes 0 0 0  
Net income (loss) 0 (9,538) 3,098  
Discontinued Operations, Disposed of by Sale | Hawkeye        
Revenues from External Customers and Long-Lived Assets [Line Items]        
Contract revenue 2,078 11,696 81,724  
Contract costs 1,317 24,728 88,514  
Amortization of intangibles 0 0 3,152  
(Gain) Loss on sale of subsidiaries 0 0 2,655  
General and administrative (370) 1,736 2,864  
Other charges 0 0    
Operating income (loss) 1,131 (14,768) (15,461)  
Non-operating income (expense) 6 (243) (159)  
Pre-tax income (loss) 1,137 (15,011) (15,620)  
Provision for income taxes 0 0 0  
Net income (loss) 1,137 (15,011) (15,620)  
Assets with respect to discontinued operations        
Cash and cash equivalents   0    
Accounts receivable, net 9 5,564    
Contract cost and recognized income not yet billed 0 66    
Prepaid expenses and other current assets 1 16    
Parts and supplies inventories   0    
Property, plant and equipment, net   511    
Intangible assets, net   0    
Other   900    
Total assets 10 7,057    
Accounts payable and accrued liabilities 452 3,970    
Contract billings in excess of costs 0 0    
Current and long-term debt 0 0    
Other current and long-term liabilities 0 1,215    
Total liabilities associated with discontinued operations 452 5,185    
Net liabilities associated with discontinued operations (442) 1,872    
Discontinued Operations, Disposed of by Sale | Other        
Revenues from External Customers and Long-Lived Assets [Line Items]        
Contract revenue 0 0 0  
Contract costs 0 0 27  
Amortization of intangibles 0 0 0  
(Gain) Loss on sale of subsidiaries 0 0 0  
General and administrative 0 0 548  
Other charges 0 0    
Operating income (loss) 0 0 (575)  
Non-operating income (expense) 0 0 125  
Pre-tax income (loss) 0 0 (450)  
Provision for income taxes 0 0 0  
Net income (loss) $ 0 $ 0 $ (450)