Consolidated Statements Of Shareholders' Equity (unaudited) Consolidated Statements Of Shareholders' Equity (unaudited) (Parenthetical) - $ / shares	3 Months Ended	6 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Purchase of treasury stock (in shares)	1,000	146,000	20,500	388,500
Dividends paid to common shareholders (per common share)	$ 0.28	$ 0.25	$ 0.55	$ 0.50

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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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 210
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration