Investment Securities - Available For Sale Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Sep. 30, 2016
Summary of amortized cost, estimated fair value and related unrealized gains and losses on securities available for sale
Amortized Cost	$ 96,328	$ 79,100
Gross Unrealized Gains	512	1,078
Gross Unrealized Losses	957	55
Estimated Fair Value	95,883	80,123
U.S. government agency obligations
Summary of amortized cost, estimated fair value and related unrealized gains and losses on securities available for sale
Amortized Cost	18,454	16,388
Gross Unrealized Gains	35	48
Gross Unrealized Losses	448	29
Estimated Fair Value	18,041	16,407
Obligations of states and political subdivisions
Summary of amortized cost, estimated fair value and related unrealized gains and losses on securities available for sale
Amortized Cost	35,656	33,405
Gross Unrealized Gains	270	630
Gross Unrealized Losses	131	23
Estimated Fair Value	35,795	34,012
Mortgage-backed securities
Summary of amortized cost, estimated fair value and related unrealized gains and losses on securities available for sale
Amortized Cost	36,661	28,861
Gross Unrealized Gains	124	389
Gross Unrealized Losses	311	3
Estimated Fair Value	36,474	29,247
Federal Agricultural Mortgage Corporation
Summary of amortized cost, estimated fair value and related unrealized gains and losses on securities available for sale
Amortized Cost		70
Gross Unrealized Gains		11
Gross Unrealized Losses		0
Estimated Fair Value		81
Trust preferred securities
Summary of amortized cost, estimated fair value and related unrealized gains and losses on securities available for sale
Amortized Cost		376
Gross Unrealized Gains		0
Gross Unrealized Losses		0
Estimated Fair Value		$ 376
Agency securities
Summary of amortized cost, estimated fair value and related unrealized gains and losses on securities available for sale
Amortized Cost	147
Gross Unrealized Gains	83
Gross Unrealized Losses	0
Estimated Fair Value	230
Corporate debt securities
Summary of amortized cost, estimated fair value and related unrealized gains and losses on securities available for sale
Amortized Cost	5,410
Gross Unrealized Gains	0
Gross Unrealized Losses	67
Estimated Fair Value	$ 5,343

This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26610-111562

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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