Consolidated Statements of Changes in Stockholders' Equity (Unaudited) (Parentheticals)	6 Months Ended
Jun. 30, 2016 $ / shares	Jun. 30, 2015 $ / shares
Additional Paid-in Capital [Member] \| Stock Split From [Member]
Stockholders' Equity Note, Stock Split, Conversion Ratio	2
Additional Paid-in Capital [Member] \| Stock Split To [Member]
Stockholders' Equity Note, Stock Split, Conversion Ratio	3
Retained Earnings [Member]
Cash dividends (in dollars per share)	$ 0.35	$ 0.31

Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB TOPIC 4.C)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187143-122770

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Stock Split
-URI http://asc.fasb.org/extlink&oid=6525746

Name:	us-gaap_StockholdersEquityNoteStockSplitConversionRatio1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration