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

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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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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
	May 31, 2022	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Oct. 18, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of common stock on restricted stock grants (in shares)		11,344
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost related to non-vested stock options granted		$ 34
Performance-based restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost related to non-vested stock options granted		$ 1,647
Awards expected to issue (in shares)		69,261,000
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
Granted (in shares)		0
Forfeited (in shares)		0
Stock option exercises (in shares)		0
Total unrecognized compensation cost related to non-vested stock options granted		$ 481
Total unrecognized compensation cost related to non-vested stock options granted, period		2 years
Intrinsic value of the stock options		$ 15,148		$ 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)	11,344,000
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		$ 426	$ 166
Pioneer's Option Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Forfeited (in shares)		261
Stock option exercises (in shares)		4,959
Intrinsic value of the stock options		$ 1,402		$ 2,263