Statement of Changes in Net Assets Available for Benefits - EBP 002 - USD ($) |
12 Months Ended | |
|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
|
| Additions | ||
| Net investment income from plan interest in the GATX Corporation Master Trust | $ 34,848,234 | $ 35,436,204 |
| Contributions | ||
| Employer contributions | 3,530,968 | 3,421,816 |
| Participant contributions | 8,479,285 | 8,255,603 |
| Rollover contributions | 515,168 | 1,080,729 |
| Total contributions | 12,525,421 | 12,758,148 |
| Interest income on notes receivable from participants | 117,285 | 111,347 |
| Transfers from GATX Corporation Hourly Employees Retirement Savings Plan | 129,477 | 168,289 |
| Total additions | 47,620,417 | 48,473,988 |
| Deductions | ||
| Participant distributions and withdrawals | 21,855,474 | 21,721,057 |
| Administrative fees | 6,475 | 6,288 |
| Total deductions | 21,861,949 | 21,727,345 |
| Net increase | 25,758,468 | 26,746,643 |
| Net assets available for benefits at beginning of year | 240,350,870 | 213,604,227 |
| Net assets available for benefits at end of year | $ 266,109,338 | $ 240,350,870 |
| X | ||||||||||
- Definition Amount of decrease in net asset available for benefit to participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Reference 1: http://www.xbrl.org/2003/role/exampleRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of decrease in net asset available for benefit from administrative expense incurred by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Reference 1: http://www.xbrl.org/2003/role/exampleRef
|
| X | ||||||||||
- Definition Amount of decrease in net asset available for benefit from payment of benefit to participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), including, but not limited to, withdrawal. Reference 1: http://www.xbrl.org/2003/role/exampleRef
|
| X | ||||||||||
- Definition Amount of increase in net asset available for benefit to participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Reference 1: http://www.xbrl.org/2003/role/exampleRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of increase (decrease) in net asset available for benefit to participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount of increase (decrease) in net asset available for benefit from increase (decrease) in plan interest in master trust held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount of increase in net asset available for benefit from contribution to employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Reference 1: http://www.xbrl.org/2003/role/exampleRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of increase in net asset available for benefit from cash contribution from employer of participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Reference 1: http://www.xbrl.org/2003/role/exampleRef
|
| X | ||||||||||
- Definition Amount of increase in net asset available for benefit from interest income on note receivable from participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Reference 1: http://www.xbrl.org/2003/role/exampleRef
|
| X | ||||||||||
- Definition Amount, excluding rollover, of increase in net asset available for benefit from contribution by participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Reference 1: http://www.xbrl.org/2003/role/exampleRef
|
| X | ||||||||||
- Definition Amount of increase in net asset available for benefit from contribution transferred from another qualified plan or from individual retirement account of participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Excludes contribution for participant transmitted by employer of participant in EBP. Reference 1: http://www.xbrl.org/2003/role/exampleRef
|
| X | ||||||||||
- Definition Amount of net asset available for benefit transferred to (from) employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) from (to) external plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
|
| X | ||||||||||
- Definition Amount of asset less liability available to pay benefit of participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), including, but not limited to, aggregation of participants' individual account balances. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Details
|