| Cover | 12 Months Ended |
| Dec. 31, 2022 | |
| Document Information [Line Items] | |
| Document Type | DEF 14A |
| Amendment Flag | false |
| Entity Information [Line Items] | |
| Entity Registrant Name | SEACOR Marine Holdings Inc. |
| Entity Central Index Key | 0001690334 |
| Pay vs Performance Disclosure - USD ($) | 12 Months Ended | |
| Dec. 31, 2022 | Dec. 31, 2021 | |
| Pay vs Performance Disclosure [Table] | ||
| Pay vs Performance [Table Text Block] | PAY VERSUS PERFORMANCE As required by Section 953(a) of the Dodd-Frank Wall Street Reform and Consumer Protection Act, and Item 402(v) of Regulation S-K, Year Summary (1) ($) Compensation (2) ($) Average Non-PEO (3) ($) Average Non-PEO (4) ($) Value of Initial Net (Loss) (6) ($) Total (5) ($) (a) (b) (c) (d) (e) (f) (g) 2022 2,755,582 5,568,170 1,518,054 2,779,848 269 (71,650,000 ) 2021 2,602,774 2,132,673 1,370,007 1,161,032 125 33,136,000 (1) The (2) The dollar amounts reported in column (c) represent the amount of “compensation actually paid” to Mr. Gellert, as computed in accordance with Item 402(v) of Regulation S-K. S-K, Year Reported Summary ($) Reported Value of Equity (a) ($) Equity Award (b) ($) Compensation ($) 2022 2,755,582 (1,544,907 ) 4,357,495 5,568,170 2021 2,602,774 (1,696,974 ) 1,226,873 2,132,673 (a) The grant date fair value of equity awards represents the total of the amounts reported in the “Stock Awards” column in the Summary Compensation Table for the applicable year. There were no “Option Awards” granted in respect of the applicable years. (b) The equity award adjustments for each applicable year include the addition (or subtraction, as applicable) of the following: (i) the year-end Year Year End ($) Year over ($) Fair ($) Year over ($) Fair Value ($) Value of ($) Total Equity ($) 2022 2,466,623 1,519,469 — 371,404 — — 4,357,495 2021 963,641 37,725 — 225,507 — — 1,226,873 (3) The dollar amounts reported in column (d) represent the average of the amounts reported for the Company’s NEOs as a group (excluding Mr. Gellert) in the “Total” column of the Summary Compensation Table in each applicable year. The names of each of the NEOs included for purposes of calculating the average amounts for both 2021 and 2022 were Jesús Llorca, Andrew H. Everett II and Gregory Rossmiller. (4) The dollar amounts reported in column (e) represent the average amount of “compensation actually paid” to the NEOs as a group (excluding Mr. Gellert), as computed in accordance with Item 402(v) of Regulation S-K. S-K, Year Average Reported Summary Total for Non-PEO NEOs ($) Average Reported Value of Equity ($) Average Equity Award (a) ($) Average Non-PEO ($) 2022 1,518,054 (749,046 ) 2,010,839 2,779,848 2021 1,370,007 (725,207 ) 516,232 1,161,032 (a) The amounts deducted or added in calculating the total average equity award adjustments are as follows: Year Average Year End Fair ($) Year over ($) Average ($) Year ($) Average ($) Average ($) Total ($) 2022 1,195,936 652,639 — 162,264 — — 2,010,839 2021 411,815 19,061 — 85,356 — — 516,232 (5) Cumulative TSR is calculated by dividing the sum of the cumulative amount of dividends for the measurement period, assuming dividend reinvestment, and the difference between the Company’s share price at the end and the beginning of the measurement period by the Company’s share price at the beginning of the measurement period. (6) The dollar amounts reported represent the amount of net income (loss) reflected in the Company’s audited financial statements for the applicabl e year. | |
| Named Executive Officers, Footnote [Text Block] | Jesús Llorca, Andrew H. Everett II and Gregory Rossmiller. | |
| PEO Total Compensation Amount | $ 2,755,582 | $ 2,602,774 |
| PEO Actually Paid Compensation Amount | $ 5,568,170 | 2,132,673 |
| Adjustment To PEO Compensation, Footnote [Text Block] | The dollar amounts reported in column (c) represent the amount of “compensation actually paid” to Mr. Gellert, as computed in accordance with Item 402(v) of Regulation S-K. S-K, Year Reported Summary ($) Reported Value of Equity (a) ($) Equity Award (b) ($) Compensation ($) 2022 2,755,582 (1,544,907 ) 4,357,495 5,568,170 2021 2,602,774 (1,696,974 ) 1,226,873 2,132,673 (a) The grant date fair value of equity awards represents the total of the amounts reported in the “Stock Awards” column in the Summary Compensation Table for the applicable year. There were no “Option Awards” granted in respect of the applicable years. (b) The equity award adjustments for each applicable year include the addition (or subtraction, as applicable) of the following: (i) the year-end Year Year End ($) Year over ($) Fair ($) Year over ($) Fair Value ($) Value of ($) Total Equity ($) 2022 2,466,623 1,519,469 — 371,404 — — 4,357,495 2021 963,641 37,725 — 225,507 — — 1,226,873 | |
| Non-PEO NEO Average Total Compensation Amount | $ 1,518,054 | 1,370,007 |
| Non-PEO NEO Average Compensation Actually Paid Amount | $ 2,779,848 | 1,161,032 |
| Adjustment to Non-PEO NEO Compensation Footnote [Text Block] | The dollar amounts reported in column (e) represent the average amount of “compensation actually paid” to the NEOs as a group (excluding Mr. Gellert), as computed in accordance with Item 402(v) of Regulation S-K. S-K, Year Average Reported Summary Total for Non-PEO NEOs ($) Average Reported Value of Equity ($) Average Equity Award (a) ($) Average Non-PEO ($) 2022 1,518,054 (749,046 ) 2,010,839 2,779,848 2021 1,370,007 (725,207 ) 516,232 1,161,032 (a) The amounts deducted or added in calculating the total average equity award adjustments are as follows: Year Average Year End Fair ($) Year over ($) Average ($) Year ($) Average ($) Average ($) Total ($) 2022 1,195,936 652,639 — 162,264 — — 2,010,839 2021 411,815 19,061 — 85,356 — — 516,232 | |
| Compensation Actually Paid vs. Total Shareholder Return [Text Block] | Compensation Actually Paid vs. Cumulative Total Shareholder Return (“TSR”) | |
| Compensation Actually Paid vs. Net Income [Text Block] | Compensation Actually Paid vs. Net Income | |
| Total Shareholder Return Amount | $ 269 | 125 |
| Net Income (Loss) | $ (71,650,000) | 33,136,000 |
| PEO Name | Mr. Gellert | |
| PEO [Member] | Reported Value of Equity Awards [Member] | ||
| Pay vs Performance Disclosure [Table] | ||
| Adjustment to Compensation Amount | $ (1,544,907) | (1,696,974) |
| PEO [Member] | Equity Award Adjustments [Member] | ||
| Pay vs Performance Disclosure [Table] | ||
| Adjustment to Compensation Amount | 4,357,495 | 1,226,873 |
| PEO [Member] | Year End Fair Value of Equity Awards [Member] | ||
| Pay vs Performance Disclosure [Table] | ||
| Adjustment to Compensation Amount | 2,466,623 | 963,641 |
| PEO [Member] | Year over Year Change in Fair Value of Outstanding and Unvested Equity Awards [Member] | ||
| Pay vs Performance Disclosure [Table] | ||
| Adjustment to Compensation Amount | 1,519,469 | 37,725 |
| PEO [Member] | Fair Value as of Vesting Date of Equity Awards Granted and Vested in the Year [Member] | ||
| Pay vs Performance Disclosure [Table] | ||
| Adjustment to Compensation Amount | 0 | 0 |
| PEO [Member] | Year over Year Change in Fair Value of Equity Awards Granted in Prior Years that Vested in the Year [Member] | ||
| Pay vs Performance Disclosure [Table] | ||
| Adjustment to Compensation Amount | 371,404 | 225,507 |
| PEO [Member] | Fair Value at the End of the Prior Year of Equity Awards that Failed to Meet Vesting Conditions in the Year [Member] | ||
| Pay vs Performance Disclosure [Table] | ||
| Adjustment to Compensation Amount | 0 | 0 |
| PEO [Member] | Value of Dividends or other Earnings Paid on Stock or Option Awards not Otherwise Reflected in Fair Value or Total Compensation [Member] | ||
| Pay vs Performance Disclosure [Table] | ||
| Adjustment to Compensation Amount | 0 | 0 |
| Non-PEO NEO [Member] | Reported Value of Equity Awards [Member] | ||
| Pay vs Performance Disclosure [Table] | ||
| Adjustment to Compensation Amount | (749,046) | (725,207) |
| Non-PEO NEO [Member] | Equity Award Adjustments [Member] | ||
| Pay vs Performance Disclosure [Table] | ||
| Adjustment to Compensation Amount | 2,010,839 | 516,232 |
| Non-PEO NEO [Member] | Year End Fair Value of Equity Awards [Member] | ||
| Pay vs Performance Disclosure [Table] | ||
| Adjustment to Compensation Amount | 1,195,936 | 411,815 |
| Non-PEO NEO [Member] | Year over Year Change in Fair Value of Outstanding and Unvested Equity Awards [Member] | ||
| Pay vs Performance Disclosure [Table] | ||
| Adjustment to Compensation Amount | 652,639 | 19,061 |
| Non-PEO NEO [Member] | Fair Value as of Vesting Date of Equity Awards Granted and Vested in the Year [Member] | ||
| Pay vs Performance Disclosure [Table] | ||
| Adjustment to Compensation Amount | 0 | 0 |
| Non-PEO NEO [Member] | Year over Year Change in Fair Value of Equity Awards Granted in Prior Years that Vested in the Year [Member] | ||
| Pay vs Performance Disclosure [Table] | ||
| Adjustment to Compensation Amount | 162,264 | 85,356 |
| Non-PEO NEO [Member] | Fair Value at the End of the Prior Year of Equity Awards that Failed to Meet Vesting Conditions in the Year [Member] | ||
| Pay vs Performance Disclosure [Table] | ||
| Adjustment to Compensation Amount | 0 | 0 |
| Non-PEO NEO [Member] | Value of Dividends or other Earnings Paid on Stock or Option Awards not Otherwise Reflected in Fair Value or Total Compensation [Member] | ||
| Pay vs Performance Disclosure [Table] | ||
| Adjustment to Compensation Amount | $ 0 | $ 0 |
