Cover Page
| Cover Page | Oct. 30, 2019 |
| Cover page. | |
| Document Type | 8-K |
| Date of Report | Oct. 30, 2019 |
| Entity Registrant Name | ALEXANDER & BALDWIN, INC. |
| Entity Incorporation, State or Country Code | HI |
| Entity File Number | 001-35492 |
| Entity Tax Identification Number | 45-4849780 |
| Entity Address, Address Line One | P. O. Box 3440, |
| Entity Address, City or Town | Honolulu, |
| Entity Address, State or Province | HI |
| Entity Address, Postal Zip Code | 96801 |
| City Area Code | (808) |
| Local Phone Number | 525-6611 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, without par value |
| Trading Symbol | ALEX |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0001545654 |
| Amendment Flag | false |