Variable Interest Entity (Details 1) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Summarized consolidated balance sheet amounts related to CCE
TOTAL ASSETS	$ 156,244	$ 146,864
CCE [Member]
Summarized consolidated balance sheet amounts related to CCE
TOTAL ASSETS	1,576	1,463
TOTAL LIABILITIES AND NONCONTROLLING INTERESTS	1,576	1,463
CCE [Member] | Cash and cash equivalents [Member]
Summarized consolidated balance sheet amounts related to CCE
TOTAL ASSETS	250	70
CCE [Member] | Trade accounts receivable [Member]
Summarized consolidated balance sheet amounts related to CCE
TOTAL ASSETS	586	623
CCE [Member] | Prepaid expenses and other current assets [Member]
Summarized consolidated balance sheet amounts related to CCE
TOTAL ASSETS	381	411
CCE [Member] | Other assets [Member]
Summarized consolidated balance sheet amounts related to CCE
TOTAL ASSETS	359	359
CCE [Member] | Current liabilities [Member]
Summarized consolidated balance sheet amounts related to CCE
TOTAL LIABILITIES AND NONCONTROLLING INTERESTS	467	513
CCE [Member] | Due to IDT Energy [Member]
Summarized consolidated balance sheet amounts related to CCE
TOTAL LIABILITIES AND NONCONTROLLING INTERESTS	2,598	1,949
CCE [Member] | Noncontrolling interests from CCE [Member]
Summarized consolidated balance sheet amounts related to CCE
TOTAL LIABILITIES AND NONCONTROLLING INTERESTS	$ (1,489)	$ (999)