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Grants For Option Equivalent

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Grants Of Full Value Awards Equivalents

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Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Number of Simulations

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Share-based Compensation Arrangement by Share-based Payment Award, Options, Assumed in Acquisition

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Share-based Compensation Arrangement by Share-based Payment Award, Other than Options, Vested and Expected to Vest, Range Based on Return on Average Assets (ROAA)

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Share-based Compensation Arrangement by Share-based Payment Award, Other than Options, Vested and Expected to Vest, Range Based on Shareholder Return

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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Share-based Compensation and Other Employment Benefit Plans (Narrative) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) simulation shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 USD ($) shares	Jan. 01, 2019	Apr. 25, 2013 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period	3 years
Options exercised (in shares) \| shares	572,000	820,000	126,000
Tax benefit recognized from compensation expense	$ 4,800	$ 6,300	$ 4,300
Unrecognized compensation cost	$ 26,100
Unrecognized compensation cost, period of recognition (years)	1 year 5 months 19 days
Stock option grants (in shares) \| shares	0	0	0
Assumed in acquisition (in shares) \| shares	0	3,230,000	0
Options outstanding, intrinsic value	$ 25,100
Options outstanding, weighted average remaining contractual term (years)	3 years 3 months 7 days
Options exercised, intrinsic value	$ 5,300	$ 13,600	$ 4,400
Performance period	3 years
Merger-Related Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 0	$ 4,219	0
FCB Financial Holdings, Inc.
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Assumed in acquisition (in shares) \| shares		3,200,000
FCB Financial Holdings, Inc. \| FCB Financial Holdings, Inc.
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Merger exchange ratio				1.055
Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	22,100
Non-option awards vested, total fair value	13,400	$ 11,200	13,600
Market Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 1,400
Number of simulations \| simulation	100,000
Non-option awards vested, total fair value	$ 3,900	2,200	5,100
Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	2,600
Non-option awards vested, total fair value	$ 4,000	$ 3,500	$ 4,300
vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
performance period
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
ROAA and ROATCE
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Minimum \| Market Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting range based on return on average assets (ROAA)	75.00%
Minimum \| Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, vested and expected to vest, range based on return on average assets	0.00%
Maximum \| Market Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting range based on return on average assets (ROAA)	125.00%
Maximum \| Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, vested and expected to vest, range based on return on average assets	150.00%
2013 Omnibus Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of authorized but unissued common stock reserved for future grants (in shares) \| shares	1,500,000				8,600,000
Grants for option equivalent (in shares) \| shares					1
Grants of full value awards equivalents (in shares) \| shares					2