Commitments and Contingencies (Details)	12 Months Ended
	Dec. 31, 2017 USD ($) employer	Dec. 31, 2016 USD ($)
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2018	$ 4,636,362
2019	3,570,048
2020	837,971
2021	7,999
Total minimum operating lease payments	9,052,380
Total rent expense	4,700,000	$ 4,800,000
Contributions to plan	$ 180,000	$ 176,000
Arrangement Expiring August 31, 2017 [Member] | Multiemployer Plan, Plan Information, Available [Member] | National Electrical Benefit Fund [Member] | Multiemployer Plans, Pension [Member]
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Number of employers responsible for 5% or more of contributions to multiemployer pension plan | employer	0
Percent of employer contribution for multiemployer pension plan (no more than 5%)	5.00%
Office space [Member]
Operating Leased Assets [Line Items]
Non-cancelable operating lease period	9 years
Office equipment [Member]
Operating Leased Assets [Line Items]
Non-cancelable operating lease period	4 years
Electrical construction equipment [Member]
Operating Leased Assets [Line Items]
Non-cancelable operating lease period	60 months