Related Party Transactions (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Summary of related party transactions
Amount IDT charged the Company	$ 377	$ 434
Amount the Company charged IDT	$ 109	$ 120

Amount of selling, general and administrative expenses resulting from transactions, excluding transactions that are eliminated in consolidated or combined financial statements, with related party.

No definition available.

Name:	us-gaap_RelatedPartyTransactionSellingGeneralAndAdministrativeExpensesFromTransactionsWithRelatedParty
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration