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Dividends and Share Repurchases (Details) - $ / shares			3 Months Ended		6 Months Ended
	Apr. 24, 2017	Feb. 10, 2017	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2017	Mar. 31, 2016
Dividends Payable [Line Items]
Cash dividends per share (in dollars per share)		$ 0.15	$ 0.40	$ 0.14	$ 0.54	$ 0.27
Special dividends declared (in dollars per share)		$ 0.25
Stock repurchased (in shares)			477
Average cost per share (in dollars per share)			$ 33.55
Warrants outstanding (in shares)			536,152		536,152
Remaining shares authorized to be repurchased (in shares)			4,157,081		4,157,081
Subsequent Event
Dividends Payable [Line Items]
Dividends declared (in dollars per share)	$ 0.15
2008 Troubled Asset Relief Program
Dividends Payable [Line Items]
Stock issued during period (in shares)			73,995

X

- Definition

Number of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
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Aggregate dividends paid during the period for each share of common stock outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Aggregate dividends declared during the period for each share of common stock outstanding.

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Number of new stock issued during the period.

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The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

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Total cost of shares repurchased divided by the total number of shares repurchased.

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Common Stock, Special Dividends, Per Share, Declared

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