Consolidated Statement of Changes in Stockholders' Equity (Parenthetical) - $ / shares	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Consolidated Statement of Changes in Stockholders' Equity [Abstract]
Purchase of treasury stock (in shares)	5,762	5,329
Cash dividends (in dollars per share)	$ 0.445	$ 0.431

Number of shares that have been repurchased during the period and are being held in treasury.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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Name:	us-gaap_TreasuryStockSharesAcquired
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration