Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2021	May 11, 2021
Entity Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Mar. 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Current Fiscal Year End Date	--12-31
Amendment Flag	false
Entity File Number	1-14180
Entity Registrant Name	LORAL SPACE & COMMUNICATIONS INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	87-0748324
Entity Address, Address Line One	600 Fifth Avenue
Entity Address, City or Town	New York
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10020
City Area Code	212
Local Phone Number	697-1105
Entity Central Index Key	0001006269
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Preferred Stock Purchase Rights [Member]
Entity Information [Line Items]
Title of 12(b) Security	Preferred Stock Purchase Rights
No Trading Symbol Flag	true
Security Exchange Name	NASDAQ
Voting Common Stock [Member]
Entity Information [Line Items]
Title of 12(b) Security	Voting Common stock, $.01 par value
Trading Symbol	LORL
Security Exchange Name	NASDAQ
Entity Common Stock, Shares Outstanding		21,427,078
Nonvoting Common Stock [Member]
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		9,505,673