Business (Details) (USD $) In Thousands, unless otherwise specified	0 Months Ended			3 Months Ended				0 Months Ended	3 Months Ended	0 Months Ended	3 Months Ended		12 Months Ended	0 Months Ended		3 Months Ended
	Feb. 14, 2013	Feb. 12, 2013	May 01, 2010	Dec. 31, 2012 numberoffacilities	Dec. 31, 2011	Sep. 30, 2012	Dec. 12, 2007	Feb. 12, 2013 Subsequent Event [Member] Amendmentto 2012creditfacility [Member]	Dec. 31, 2012 Subsequent Event [Member] Amendmentto 2012creditfacility [Member]	Feb. 12, 2013 Subsequent Event [Member] WellsFargoTermLoan [Member]	Dec. 31, 2012 Subsequent Event [Member] Business Acquisition Acro Member [Member]	Dec. 31, 2012 Tontine Associates [Member]	Sep. 30, 2012 Commercial Real Estate [Member]	Dec. 10, 2010 Sale of Non-Strategic Manufacturing Facility	Feb. 28, 2011 Non- Core Electrical Distribution Facility	Dec. 31, 2012 Communications [Member]	Dec. 31, 2011 Communications [Member]	Dec. 31, 2012 Residential [Member] numberoffacilities	Dec. 31, 2011 Residential [Member]	Dec. 31, 2012 Commercial & Industrial [Member] numberoffacilities	Dec. 31, 2011 Commercial & Industrial [Member]
Business Transactions [Line Items]
Sale price of facility														$ 10,086
Gain on sale of facility														6,763	6,676
Lease expiration date												Mar. 31, 2014
Monthly Lease Payments												6
Lease inception date												Apr. 01, 2012
Revenues				127,264	108,998											40,119	25,162	36,005	29,272	51,140	54,564
Fair value of the Tontine Term Loan				10,157
Fair value of our investment in EnerTech				919		919
Impairment of Real Estate													688
Tontine - Beginning Balance							25,000
Repayments of Subordinated Debt	10,000		15,000
Tontine - Ending Balance	0						25,000
Locations [Line Items]
Number of locations				61												10,000		32		19
Subsequent Event [Line Items]
Business Acquisition, Name of Acquired Entity				Acro Group
Business Acquisition, Description of Acquired Entity											a group of entities operating under the name of Acro Group: Residential Renewable Technologies, Inc., Energy Efficiency Solar, Inc. and Lonestar Renewable Technologies Acquisition Corp.
Business Combination, Reason for Business Combination											will offer full-service residential solar integration services, including design, procurement, permitting, installation, financing services through third parties and warranty services for residential customers.
Business Acquisition, Preexisting Relationship, Description											IES Residential has previously provided solar installation subcontracting services to the Acro Group
Line of Credit Facility, Increase, Additional Borrowings		$ 5,000
Line of Credit Facility, Description									On February 12, 2013, we entered into an amendment of our 2012 Credit Facility (the “Amendment”). Pursuant to the Amendment, Wells Fargo Bank, National Association (“Wells Fargo”) has provided the Company with a $5,000 term loan (the “Wells Fargo Term Loan”). While the Term Loan bears interest at a per annum rate equal to Daily Three Month LIBOR plus 6.00%, the Company and Wells Fargo intend to enter into an interest rate swap, whereby the Company will cause the interest rate for borrowings under the Term Loan to be fixed at 7.00% per annum. Interest and principal payments are due in monthly installments over a 24-month period. The Company may prepay the Wells Fargo Term Loan in part or in whole prior to its stated maturity upon the payment of the outstanding principal amount, accrued but unpaid interest and prepayment fees. The Amendment extends the term of the 2012 Credit Facility to August 9, 2016 and adds IES Renewable Energy, LLC as a borrower on the 2012 Credit Facility.
Line Of Credit Facility Initiation Date 1								Feb. 12, 2013
Line Of Credit Facility Expiration Date 1								Aug. 09, 2016
Line of Credit Facility, Interest Rate Description										interest at a per annum rate equal to Daily Three Month LIBOR plus 6.00%, the Company and Wells Fargo intend to enter into an interest rate swap, whereby the Company will cause the interest rate for borrowings under the Term Loan to be fixed at 7.00% per annum.
TermLoanEndingInterestRate										7
Line of Credit Facility, Frequency of Payment and Payment Terms										Interest and principal payments are due in monthly installments over a 24-month period.
Line of Credit Facility, Frequency of Payments										monthly