Regulatory Matters - Guidelines Governing the Classification of Capital Tiers (Details)	Jun. 30, 2018
Banking and Thrift [Abstract]
Tier 1 Capital to Average Assets (Leverage), Well capitalized	5.00%
Tier 1 Capital to Average Assets (Leverage), Adequately capitalized	4.00%
Tier 1 Capital to Average Assets (Leverage), Undercapitalized	4.00%
Tier 1 Capital to Average Assets (Leverage), Significantly undercapitalized	3.00%
Common Equity Tier 1 to Risk-Weighted Assets, Well capitalized	6.50%
Common Equity Tier 1 to Risk-Weighted Assets, Adequately capitalized	4.50%
Common Equity Tier 1 to Risk-Weighted Assets, Undercapitalized	4.50%
Common Equity Tier 1 to Risk-Weighted Assets, Significantly undercapitalized	3.00%
Tier 1 Capital to Risk-Weighted Assets, Well capitalized	8.00%
Tier 1 Capital to Risk-Weighted Assets, Adequately capitalized	6.00%
Tier 1 Capital to Risk-Weighted Assets, Undercapitalized	6.00%
Tier 1 Capital to Risk-Weighted Assets, Significantly undercapitalized	4.00%
Total Capital to Risk-Weighted Assets, Well capitalized	10.00%
Total Capital to Risk-Weighted Assets, Adequately capitalized	8.00%
Total Capital to Risk-Weighted Assets, Undercapitalized	8.00%
Total Capital to Risk-Weighted Assets, Significantly undercapitalized	6.00%
Critically undercapitalized	2.00%

Capital Required to be Significantly Undercapitalized to Risk Weighted Assets

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Capital Required to be Undercapitalized to Risk Weighted Assets

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Common Equity Tier One Leverage Capital Required For Capital Adequacy To Average Assets

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Common Equity Tier One Leverage Capital Required To Be Significantly Undercapitalized to Average Assets

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Common Equity Tier One Leverage Capital Required To Be Undercapitalized To Average Assets

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Common Equity Tier One Leverage Capital To Average Assets

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Tangible Capital Required to be Critically Undercapitalized to Total Assets

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Tier One Leverage Capital Required to be Significantly Undercapitalized to Average Assets

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Tier One Leverage Capital Required to be Undercapitalized to Average Assets

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Tier One Risk Based Capital Required to be Significantly Undercapitalized to Risk Weighted Assets

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Tier One Risk Based Capital Required to be Undercapitalized to Risk Weighted Assets

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The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Name Accounting Standards Codification
-Topic 942
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-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958570-112826

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The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

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The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations.

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized divided by average assets as defined in the regulatory framework for prompt corrective action.

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The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958570-112826

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1H
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826

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The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

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