CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (Parentheticals) - $ / shares	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY
Issuance of common stock to non-employee directors (in shares)	5,556	5,814
Dividends paid (in dollars per share)	$ 0.18	$ 0.18

Net number of share options (or share units) granted during the period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration