Duration of performance evaluation for stock units to vest.

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Payment Deferral Period

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- Definition

Percentage of performance conditions achieved.

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- Definition

Length of time after vesting PSUs are required to be held.

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Quarterly value of shares available for purchase under dividend reinvestment and stock purchase plan.

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Share-based Compensation Arrangement by Share-based Payment Award, Number Of Plans

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Value of annual equity awards to non employee directors.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock Options, Restricted Stock, and Dividend Reinvestment Plans - Narrative (Details)	12 Months Ended
	Dec. 31, 2018 USD ($) plan $ / shares shares	Dec. 31, 2017 USD ($) $ / shares shares	Dec. 31, 2016 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of plans \| plan	1
Options granted (in shares) \| shares	1,260,143
Number of shares available for grant (in shares) \| shares	6,810,413
Award vesting period	3 years
Payment deferral period	2 years
Value of annual equity awards to non employee directors	$ 65,000	$ 65,000
Total intrinsic value of options exercised	$ 3,000,000	$ 2,500,000	$ 10,600,000
Stock options granted or converted (in shares) \| shares	394,296	1,483,323	971,328
Grants in period, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 3.89	$ 4.69	$ 2.95
Stock-based compensation expense	$ 23,171,000	$ 20,627,000	$ 17,536,000
Total income tax benefits recognized	$ 5,700,000	7,900,000	6,700,000
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	1 year
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
Stock Appreciation Rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares) \| shares	0
Nonvested Restricted Stock Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee service share-based compensation, nonvested awards, compensation cost not yet recognized	$ 27,800,000
Employee service share-based compensation, nonvested awards, compensation cost not yet recognized, period for recognition	2 years 3 months
Total grant date fair value of shares vested	$ 12,600,000	$ 9,900,000	$ 9,700,000
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee service share-based compensation, nonvested awards, compensation cost not yet recognized	$ 1,800,000
Employee service share-based compensation, nonvested awards, compensation cost not yet recognized, period for recognition	2 years 9 months
Expiration period	20 years
Equity Compensation Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (in shares) \| shares	8,729,408
Performance Condition Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Duration of performance evaluation		3 years	3 years
Performance Condition Awards \| PSUs Granted After 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Post vest holding period	2 years
Percent of performance condition achieved	10830.00%
Market Condition Award \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	7 years
Dividend Reinvestment Plan \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Quarterly value of shares available for purchase under dividend reinvestment and stock purchase plan	$ 25
Dividend Reinvestment Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Quarterly value of shares available for purchase under dividend reinvestment and stock purchase plan	$ 10,000
Capital Bank Financial Corporation \| Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period	10 years
Options Granted Since 2008 \| Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period	7 years