Quarterly report pursuant to Section 13 or 15(d)

Business Segment Information (Details)

v3.7.0.1
Business Segment Information (Details) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2017
Jun. 30, 2016
Jun. 30, 2017
Jun. 30, 2016
Segment Reporting Information [Line Items]        
Revenues $ 166,665 $ 162,628 $ 301,275 $ 296,404
Interest income 27 13 46 24
Interest expense 2,271 1,760 4,119 3,234
Depreciation and amortization of intangible assets 5,659 5,528 11,406 10,949
Income (loss) before taxes, excluding unallocated corporate activity 14,226 9,705 18,723 18,377
Canada        
Segment Reporting Information [Line Items]        
Unallocated corporate activity   (1,934)    
Operating Segments | U.S. Regions        
Segment Reporting Information [Line Items]        
Revenues 60,979 70,583 102,585 112,204
Interest income 0 0 0 0
Interest expense 0 0 0 0
Depreciation and amortization of intangible assets 67 137 141 274
Income (loss) before taxes, excluding unallocated corporate activity 2,412 4,623 (169) 4,814
Operating Segments | U.S. Federal        
Segment Reporting Information [Line Items]        
Revenues 59,106 43,099 107,030 81,768
Interest income 9 3 15 5
Interest expense 266 289 533 388
Depreciation and amortization of intangible assets 654 704 1,307 1,227
Income (loss) before taxes, excluding unallocated corporate activity 8,881 4,565 14,326 10,965
Operating Segments | Canada        
Segment Reporting Information [Line Items]        
Revenues 8,991 13,198 18,492 28,005
Interest income 0 0 1 0
Interest expense 487 403 934 750
Depreciation and amortization of intangible assets 286 261 575 500
Income (loss) before taxes, excluding unallocated corporate activity 614 (1,844) 101 (1,303)
Operating Segments | Small-Scale Infrastructure        
Segment Reporting Information [Line Items]        
Revenues 19,066 19,060 37,594 39,753
Interest income 18 10 30 19
Interest expense 1,505 1,068 2,627 2,096
Depreciation and amortization of intangible assets 4,220 3,751 8,473 7,600
Income (loss) before taxes, excluding unallocated corporate activity 1,903 2,290 3,152 4,611
Operating Segments | Other        
Segment Reporting Information [Line Items]        
Revenues 18,523 16,688 35,574 34,674
Interest income 0 0 0 0
Interest expense 13 0 25 0
Depreciation and amortization of intangible assets 432 675 910 1,348
Income (loss) before taxes, excluding unallocated corporate activity 416 71 1,313 (710)
Unallocated corporate activity        
Segment Reporting Information [Line Items]        
Unallocated corporate activity (7,206) (6,839) (14,092) (14,566)
Unallocated corporate activity | U.S. Regions        
Segment Reporting Information [Line Items]        
Unallocated corporate activity 0 0 0 0
Unallocated corporate activity | U.S. Federal        
Segment Reporting Information [Line Items]        
Unallocated corporate activity 0 0 0 0
Unallocated corporate activity | Canada        
Segment Reporting Information [Line Items]        
Unallocated corporate activity 0 0 0 0
Unallocated corporate activity | Small-Scale Infrastructure        
Segment Reporting Information [Line Items]        
Unallocated corporate activity 0 0 0 0
Unallocated corporate activity | Other        
Segment Reporting Information [Line Items]        
Unallocated corporate activity $ 0 $ 0 $ 0 $ 0