Income Taxes (Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Income Taxes [Abstract]
Unrecognized tax benefits	$ (2,467)	$ 41,115
Interest income (expense)	(1,570)	6,752
Total	$ (4,037)	$ 47,867

The total increases and decreases to income tax liability, interest expense and penalties expense computed by applying the applicable statutory rates for tax, interest and penalties to the difference between a tax position recognized for financial reporting purposes and the amount previously taken or expected to be taken in a tax return of the entity.

No definition available.

Name:	lorl_TotalIncomeTaxInterestAndPenaltiesExpenseOnUncertainTaxPositions
Namespace Prefix:	lorl_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration