Note 11 - Net Income (Loss) Per Common Share - Earnings Per Share, Basic and Diluted (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Net income (loss) attributable to JMP Group LLC	$ 3,628	$ 1,124	$ 4,717	$ (10,624)
Basic (in shares)	19,861	19,582	19,842	19,557
Restricted share units and share options (in shares)	1,182	162	1,028	0
Diluted weighted average shares outstanding (in shares)	21,043	19,744	20,870	19,557
Basic (in dollars per share)	$ 0.18	$ 0.06	$ 0.24	$ (0.54)
Diluted (in dollars per share)	$ 0.17	$ 0.06	$ 0.23	$ (0.54)

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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