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Regulatory & Capital Matters - Dividend Restrictions and Deferrals (Details)	3 Months Ended
	Mar. 31, 2018
Dividend Restrictions and Deferrals
Number of previous years retained profit considered for dividend payment	2 years
Minimum capital requirements, minimum percentage required, 2016	0.625%
Minimum capital requirements, minimum percentage required, 2017	1.25%
Minimum capital requirements, minimum percentage required, 2018	1.875%
Minimum capital requirements, minimum percentage required, 2019 and thereafter	2.50%

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- Definition

Represents the number of previous years retained profits combined with the current years profits used to determine the amount of dividends that may be paid in any calendar year.

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The minimum percentage of Tier 1 Common Capital required to be maintained in the next fiscal year following the latest fiscal year to prevent capital distribution limitations under regulatory capital rules.

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The minimum percentage of Tier 1 Common Capital required to be maintained in year four and thereafter following the latest fiscal year to prevent capital distribution limitations under regulatory capital rules.

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No definition available.

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The minimum percentage of Tier 1 Common Capital required to be maintained in year three following the latest fiscal year to prevent capital distribution limitations under regulatory capital rules.

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No definition available.

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- Definition

The minimum percentage of Tier 1 Common Capital required to be maintained in year two following the latest fiscal year to prevent capital distribution limitations under regulatory capital rules.

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No definition available.

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