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Common Equity Tier One Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets

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Common Equity Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets

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Minimum requirement of capital conservation buffer ratio.

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Percentage of shares repurchased among authorized.

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Regulatory capital modified transition amount percentage.

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Regulatory capital transition percentage.

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

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- Definition

Ratio of minimum total risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

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Ratio of minimum total risk-based capital to risk-weighted assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

The cash outflow to reacquire common stock during the period.

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The net cash inflow or outflow resulting from the entity's share transaction.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

Amount of stock repurchase plan authorized.

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Expiration date for the purchase of an entity's own shares under a stock repurchase plan, in the CCYY-MM-DD format.

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The 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.

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Ratio of minimum Tier 1 leverage capital to average assets required for capital adequacy as defined by regulatory framework.

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Ratio of minimum Tier 1 leverage capital to average assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.

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Ratio of minimum Tier 1 risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

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Ratio of minimum Tier 1 risk-based capital to risk-weighted assets categorized as well capitalized as defined by regulatory framework for prompt corrective action.

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

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Cost basis for treasury stock acquired for purposes other than retirement.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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Stockholders' Equity (Narrative) (Details) $ / shares in Units, $ in Thousands					1 Months Ended	12 Months Ended
	Mar. 18, 2020 USD ($) shares	Oct. 21, 2019 USD ($) shares	Sep. 23, 2019 shares	Sep. 21, 2019 USD ($) shares	Jan. 31, 2020 $ / shares shares	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 USD ($)	Mar. 27, 2020	Oct. 18, 2019 USD ($)	Jan. 01, 2019
Equity, Class of Treasury Stock [Line Items]
Treasury stock shares						4,500,000	4,000,000.0
Treasury stock, Cost basis \| $						$ 150,700	$ 135,800
Payments for repurchase of common stock \| $						$ 12,716		$ 8,267
Shares repurchased							3,611,870
Initial delivery of shares under accelerated share repurchase agreement, shares							3,611,870
Minimum risk-based capital ratio						8.00	8.00	0.080
Minimum Tier 1 common equity						4.50%	4.50%	4.50%
Minimum Tier 1 capital ratio						6.00	6.00	0.060
Minimum Tier 1 leverage capital ratio						4.00	4.00	0.040
Well capitalized total risk based capital ratio						10.00	10.00	10.0
Well capitalized Tier 1 common equity						6.50%	6.50%	6.50%
Well capitalized Tier 1 risk-based capital ratio						8.00	8.00	8.0
Well capitalized Tier 1 leverage capital ratio						5.00	5.00	5.0
Minimum requirement of capital conservation buffer ratio											2.50%
Bank Holding Companies and Banks that Meet Certain Criteria [Member]
Equity, Class of Treasury Stock [Line Items]
Minimum Tier 1 leverage capital ratio								0.030
Topic 326 [Member]
Equity, Class of Treasury Stock [Line Items]
Regulatory Capital Modified Transition Amount Percentage									25.00%
Topic 326 [Member] \| Regulatory Capital Transition For First Two Years [Member]
Equity, Class of Treasury Stock [Line Items]
Regulatory Capital Transition Percentage									0.00%
Topic 326 [Member] \| Regulatory Capital Three Year Transition, Year 2022 [Member]
Equity, Class of Treasury Stock [Line Items]
Regulatory Capital Transition Percentage									25.00%
Topic 326 [Member] \| Regulatory Capital Three Year Transition, Year 2023 [Member]
Equity, Class of Treasury Stock [Line Items]
Regulatory Capital Transition Percentage									50.00%
Topic 326 [Member] \| Regulatory Capital Three Year Transition, Year 2024 [Member]
Equity, Class of Treasury Stock [Line Items]
Regulatory Capital Transition Percentage									75.00%
Topic 326 [Member] \| Regulatory Capital Three Year Transition, Year 2024 and Thereafter [Member]
Equity, Class of Treasury Stock [Line Items]
Regulatory Capital Transition Percentage									100.00%
Accelerated Share Repurchase Agreement \| Common Stock [Member]
Equity, Class of Treasury Stock [Line Items]
Share repurchase, authorized amount \| $						$ 5,500				$ 185,000
Payments for repurchase of common stock \| $		$ 185,000
Shares repurchased	1,001,472	3,611,870			315,851	4,900,000
Percentage of shares repurchased among authorized		75.00%
Proceeds from repurchase of common stock \| $	$ 12,100
Initial delivery of shares under accelerated share repurchase agreement, shares	1,001,472	3,611,870			315,851	4,900,000
Shares purchased price per share \| $ / shares					$ 40.26	$ 37.65
2018 Stock Buyback Program [Member]
Equity, Class of Treasury Stock [Line Items]
Number of shares authorized for repurchase			5,500,000
Stock repurchase expiration date			Dec. 31, 2020
MidSouth [Member]
Equity, Class of Treasury Stock [Line Items]
Business combination, number of common stock issued				5,044,332
Business combination, common stock value \| $				$ 193,800
Restricted Stock [Member]
Equity, Class of Treasury Stock [Line Items]
Number of shares nonvested						1,700,000	1,400,000