Share-Based Compensation Arrangement By Share-Based Payment Award, Awards Expected To Issue

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- Definition

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

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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 cost to be recognized for option under share-based payment arrangement.

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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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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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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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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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

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Stockholders' Equity - Narrative (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended				9 Months Ended
	May 31, 2023	May 31, 2022	Sep. 30, 2023	Jun. 30, 2023	Sep. 30, 2022	Jun. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of common stock on restricted stock grants (in shares)				15,007		11,344
Share-based payment arrangement, compensation cost							$ 1,743	$ 1,093
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost related to non-vested stock options granted			$ 236				236
Performance-based restricted stock \| May 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost related to non-vested stock options granted			$ 2,342				$ 2,342
Awards expected to issue (in shares)			100,373				100,373
Performance-based restricted stock \| May 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost related to non-vested stock options granted			$ 1,225				$ 1,225
Awards expected to issue (in shares)			68,881				68,881
Option awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)							0
FirstSun Capital Bancorp 2017 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate shares of common stock (in shares)			1,977,292				1,977,292
Granted (in shares)			0				0
Forfeited (in shares)			0				0
Stock option exercises (in shares)			0				0
Total unrecognized compensation cost related to non-vested stock options granted			$ 243				$ 243
Total unrecognized compensation cost related to non-vested stock options granted, period							2 years
Intrinsic value of the stock options			$ 11,891				$ 11,891		$ 21,216
FirstSun Capital Bancorp 2021 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate shares of common stock (in shares)										2,476,571
Issuance of common stock on restricted stock grants (in shares)	15,007	11,344
Pioneer's Option Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Forfeited (in shares)			1,044				6,525
Stock option exercises (in shares)			22,972				32,107
Intrinsic value of the stock options			$ 823				$ 823		$ 2,263
FirstSun Capital Bancorp 2017 And 2021 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, compensation cost			$ 660		$ 473