Significant Accounting Policies (Schedule of Deferred Revenue in Consolidated Balance Sheets) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Significant Accounting Policies [Abstract]
Beginning of year	$ 2,606	$ 1,824
Deferral of revenue	1,864	2,084
Recognition of deferred revenue	(1,936)	(1,302)
Balance at end of year	$ 2,534	$ 2,606

Amount of deferred revenue recognized for transactions arising during the current reporting period. Deferred revenue is a liability as of the balance sheet date related to a revenue producing activity for which revenue has not yet been recognized. Generally, an Entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

No definition available.

Name:	us-gaap_DeferredRevenueAdditions
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration