v3.25.3

Stockholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended						9 Months Ended		12 Months Ended
	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024	May 01, 2025	May 04, 2023	May 04, 2022
Class of Stock [Line Items]
Preferred stock, Dividend rate percentage							6.625%		6.625%
Dividends, Preferred Stock	$ 1,855	$ 1,855	$ 1,855	$ 1,855	$ 1,855	$ 1,855
Maximum number of shares issued under Equity Incentive Plan										5,763,580		3,763,580
Stock Repurchase Program, Authorized Amount											$ 50,000
Stock Repurchased During Period, Shares							0	0
Dividends, Common Stock		$ 4,036	$ 4,036	$ 4,015	$ 4,015	$ 4,015
Schedule of Share Based Compensation Arrangement by Share Based Payment Award For Defined Performance							The payouts under the Performance RSU Awards are evaluated on a sliding scale as follows: TSR below the 30th percentile of the Peer Group would result in a 50% payout; TSR at the 50th percentile of the Peer Group would result in a 100% payout; and TSR at or above the 75th percentile of the Peer Group would result in a 150% payout. Payouts are mathematically interpolated between these stated percentile targets, subject to a 150% maximum
Series A Preferred Stock [Member] \| S 2025 Q3 Dividends [Member]
Class of Stock [Line Items]
Preferred stock, Dividend rate percentage	6.625%
Preferred Stock [Member] \| S 2025 Q3 Dividends [Member]
Class of Stock [Line Items]
Dividends, preferred stock, cash	$ 1,900
Dividends paid, declared date	Sep. 15, 2025
Declared cash dividend distribution per share	$ 0.4140625						$ 0.4140625
Dividends paid date	Oct. 24, 2025
Dividends paid, date of record	Oct. 10, 2025
Executive Officer [Member]
Class of Stock [Line Items]
Share-based Payment Award, Award Vesting Period							3 years

Performance RSU Award payout based on the total stockholder return ("TSR") of the Company's common stock over a three-year measurement period beginning January 1, 2020 and ending on December 31, 2022 relative to the TSR of the companies in the SNL US REIT Office index as of January 2, 2020."

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City Office REIT, Inc. 10-Q