Long-Term Debt (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Susquehanna Bank [Member] | Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Principal amount of the line of credit	$ 7,500,000
Line of Credit Facility, Affiliated Borrower	GSE Systems, Inc. and GSE Performance Solutions, Inc.
Line of Credit Facility, Interest Rate Description	Working capital advances bear interest at a rate equal to the Wall Street Journal Prime Rate of Interest, floating with a floor of 4 1/2%
Expiration date of credit agreement	Mar. 31, 2015
Minimum Cash Balance Requirement	3,000,000
Number of consecutive quarters entity must attain positive net income	2
Issuances of stand-by letters of credit and advances as of period end	4,200,000
Susquehanna Bank [Member] | Revolving Credit Facility [Member] | Cash flow coverage ratio [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Covenant Terms	Must Exceed 1.20 : 1.00
Line of Credit Facility, Covenant Compliance	-12.11 : 1.00
Susquehanna Bank [Member] | Revolving Credit Facility [Member] | Minimum tangible capital base [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Covenant Terms	Must Exceed $26.0 million
Line of Credit Facility, Covenant Compliance	$15.4 million
Susquehanna Bank [Member] | Revolving Credit Facility [Member] | Quick Ratio [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Covenant Terms	Must Exceed 2.00 : 1.00
Line of Credit Facility, Covenant Compliance	1.57 : 1.00
Susquehanna Bank [Member] | Revolving Credit Facility [Member] | Tangible capital base ratio [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Covenant Terms	Not to Exceed .75 : 1.00
Line of Credit Facility, Covenant Compliance	1.44 : 1.00
IberiaBank [Member] | Line of Credit [Member]
Line of Credit Facility [Line Items]
Principal amount of the line of credit		1,000,000
Line of Credit Facility, Affiliated Borrower		Hyperspring, LLC
Line of Credit Facility, Interest Rate Description	interest is payable monthly at a rate of the prime rate of interest as published in the money rate section of the Wall Street Journal plus 1.00 %
Line of Credit Facility, Interest Rate During Period	4.25%
Line of Credit Facility, Collateral	The line is secured by all accounts and guaranteed by GSE Systems, Inc.
Line of credit facility term		0 years 5 months 9 days
Expiration date of credit agreement		Jun. 30, 2015
Line of Credit Facility, Fair Value of Amount Outstanding	$ 339,000