CONSOLIDATED BALANCE SHEETS (Parentheticals) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Class of Stock [Line Items]
Common Stock, Value	$ 1,425	$ 1,437
Common Class A [Member]
Class of Stock [Line Items]
Common Stock, Value	1,385	1,397
Common Class B [Member]
Class of Stock [Line Items]
Common Stock, Value	40	40
Common Class C Member
Class of Stock [Line Items]
Common Stock, Value	$ 0	$ 0

Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Name:	us-gaap_CommonStockValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant