Business combination transaction value on average of share price.

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

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- Definition

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

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No definition available.

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- Definition

Minimum requirement of capital conservation buffer ratio.

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- Definition

Percentage of shares repurchased among authorized.

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No definition available.

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Repurchased shares treated as forward contract for final settlement value.

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- Definition

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

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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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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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- 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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- Definition

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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No definition available.

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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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No definition available.

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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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- Definition

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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- Definition

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.

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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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- Definition

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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- Definition

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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The amount allocated to treasury stock. Treasury stock is common and preferred shares of an entity that were issued, repurchased by the entity, and are held in its treasury.

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Stockholders' Equity (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands				12 Months Ended		17 Months Ended
	Oct. 21, 2019	Sep. 23, 2019	Sep. 21, 2019	Dec. 31, 2019	Dec. 31, 2018	Sep. 30, 2019	Oct. 18, 2019	Jan. 01, 2019
Equity, Class of Treasury Stock [Line Items]
Treasury stock shares				4,000,000.0	900,000
Treasury stock, Cost basis				$ 135,800	$ 18,500
Payments for repurchase of common stock				$ 185,000	$ 8,267
Shares repurchased				3,611,870
Minimum risk-based capital ratio				8.00%	8.00%
Minimum Tier 1 common equity				4.50%	4.50%
Minimum Tier 1 capital ratio				6.00%	6.00%
Minimum Tier 1 leverage capital ratio				4.00%	4.00%
Well capitalized total risk based capital ratio				10.00%	10.00%
Well capitalized Tier 1 common equity				6.50%	6.50%
Well capitalized Tier 1 risk-based capital ratio				8.00%	8.00%
Well capitalized Tier 1 leverage capital ratio				5.00%	5.00%
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					3.00%
Accelerated Share Repurchase Agreement \| Common Stock [Member]
Equity, Class of Treasury Stock [Line Items]
Share repurchase, authorized amount							$ 185,000
Payments for repurchase of common stock	$ 185,000
Shares repurchased	3,611,870
Percentage of shares repurchased among authorized	75.00%
Treasury stock, value	$ 138,800
Repurchased shares treated as forward contract for final settlement value	$ 46,200
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
Shares repurchased						200,000
Shares purchased price per share						$ 41.30
MidSouth [Member]
Equity, Class of Treasury Stock [Line Items]
Business combination, number of common stock issued			5,044,332,000,000	5,000,000.0
Business combination, common stock value			$ 193,800	$ 193,800
Restricted Stock [Member]
Equity, Class of Treasury Stock [Line Items]
Number of shares nonvested				1,400,000	1,300,000