Preferred Stock Depository Share

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- Definition

Preferred Stock, Ownership Interest, Percentage

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- Definition

Restricted Stock Amortization

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No definition available.

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Vesting period of time-based restricted stock, higher limit

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Vesting period of time-based restricted stock, lower limit

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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- Definition

Rate of interest on investment.

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- Definition

The cash outflow for cost incurred directly with the issuance of an equity security.

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- Definition

The per share liquidation preference (or restrictions) of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share.

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- Definition

Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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- Definition

Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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Aggregate par or stated value of issued nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable preferred shares, par value and other disclosure concepts are in another section within stockholders' equity.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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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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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Number of shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Percentage of vesting of award under share-based payment arrangement.

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- Definition

Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

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Stockholders' Equity - Narrative (Details)	3 Months Ended		6 Months Ended
Stockholders' Equity - Narrative (Details)	Jun. 30, 2022 USD ($) $ / shares shares	Jun. 30, 2021 USD ($)	Jun. 30, 2022 USD ($) $ / shares shares	Jun. 30, 2021 USD ($)	Jun. 06, 2022 USD ($) $ / shares shares	Dec. 31, 2021 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Stock Amortization \| $	$ 9,000,000	$ 8,200,000	$ 16,500,000	$ 14,600,000
Unvested restricted shares (shares) \| shares	2,516,279		2,516,279			2,312,080
Vesting period of time-based restricted stock, lower limit			3 years
Preferred stock issued (shares) \| shares					20,530,000
Preferred Stock, Liquidation Preference Per Share \| $ / shares					$ 1,000
Preferred Stock Depository Share \| $	$ 25.00		$ 25.00
Payments of Stock Issuance Costs \| $	$ 14,700,000
Preferred stock par value (usd per share) \| $ / shares	$ 0.01		$ 0.01			$ 0.01
Preferred stock ($0.01 par value; 5,000,000 shares authorized; 513,250 Series A shares, \| $	$ 498,516,000		$ 498,516,000		$ 513,300,000	$ 0
Stock Issued During Period, Value, New Issues \| $	$ 498,516,000
1/40th Ownership Interest					0.025
Preferred Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Investment Interest Rate					7.75%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of time-based restricted stock, higher limit			4 years
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested restricted shares (shares) \| shares	505,647		505,647
Vesting term			3 years
Performance Shares \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			0.00%
Performance Shares, One \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			150.00%
Performance Shares, Two \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			200.00%
PacWest 2017 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (shares) \| shares	2,083,271		2,083,271
Unrecognized share based compensation expense \| $	$ 82,300,000		$ 82,300,000
PacWest 2017 Stock Incentive Plan [Member] \| Time-Based Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested restricted shares (shares) \| shares	2,516,279		2,516,279
PacWest 2017 Revised Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (shares) \| shares	6,650,000		6,650,000