Debt (Narrative) (Details)		6 Months Ended	12 Months Ended
	Jan. 30, 2018 USD ($) Installment	Jun. 30, 2018 USD ($)	Dec. 31, 2017	Dec. 31, 2016 USD ($)
Affiliated Entity [Member] | Revolving Line of Credit [Member]
Debt Instrument [Line Items]
Line of credit aggregate borrowing capacity				$ 1,500,000
Interest rate description		Aggregate loans under the Line of Credit up to $1.0 million incur interest at a variable rate per annum based on the rate charged to the Entity by its bank, plus 2.0%. Amounts outstanding at any time in excess of $1.0 million incur interest at a rate of 8.0% per annum.
Line of credit, annual commitment fee				$ 15,000
Line of credit, commitment fee payment description		monthly basis
Maturity description		The Line of Credit matures at the earlier of (i) three years from the date of the Agreement, (ii) the termination of the Entity’s line of credit with its bank, or (iii) forty-five (45) days following the date the Company closes a new credit facility with a financial institution. During the six months ended June 30, 2018, the Company had not drawn on the Line of Credit. Refer to Note 10 Subsequent Events for further discussion of the Company’s Line of Credit.
Heritage Global LLC [Member]
Debt Instrument [Line Items]
Litigation settlement, amount paid behalf of subsidiary	$ 1,260,000
Number of installments | Installment	36
Litigation settlement installments amount due	$ 35,000
Remaining outstanding debt balance payable date	Jan. 30, 2021
Interest rate on promissory note			6.50%
Percentage of default interest amount		12.00%
Description of event of default		An “Event of Default” means: (a) any failure of HGLLC to pay when due any amount thereunder, when and as due, (b) any failure on the part of HGLLC to pay upon 54 Finance’s demand any fees, costs, expenses or other charges hereunder or otherwise due to HGLLC under the Note or the Guaranty, (c) any breach, failure or default under the Guaranty, (d) HGLLC or HGI repudiates or revokes, or purports to repudiate or revoke, any obligation under the Note or the Guaranty, or the obligation of HGI under the Guaranty is limited or terminated by operation of law or by HGI, or (e) HGLLC or HGI are insolvent or admit in writing its inability to pay debts as they mature, or make a general assignment for the benefit of its creditors, or institute any bankruptcy, insolvency or similar proceeding under the laws of any jurisdiction, or take any action to authorize such proceeding. During the six months ended June 30, 2018, the Company made the first five payments on the Note totaling $175,000
Debt instrument, periodic payment		$ 175,000,000
Bank Plus 2.0% [Member] | Affiliated Entity [Member] | Revolving Line of Credit [Member]
Debt Instrument [Line Items]
Interest rate per annum				2.00%
Bank Plus 2.0% [Member] | Affiliated Entity [Member] | Revolving Line of Credit [Member] | Maximum [Member]
Debt Instrument [Line Items]
Line of credit				$ 1,000,000
8.0% Interest Rate [Member] | Affiliated Entity [Member] | Revolving Line of Credit [Member]
Debt Instrument [Line Items]
Related party loan, Interest rate				8.00%
8.0% Interest Rate [Member] | Affiliated Entity [Member] | Revolving Line of Credit [Member] | Minimum [Member]
Debt Instrument [Line Items]
Line of credit				$ 1,000,000
Street Capital Loan [Member]
Debt Instrument [Line Items]
Related party loan, Interest rate		5.75%	5.50%
Street Capital Loan [Member] | Wall Street Journal prime rate [Member]
Debt Instrument [Line Items]
Interest rate per annum				1.00%