| Cover Page | Feb. 03, 2021 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Feb. 3, 2021 |
| Entity Registrant Name | GLACIER BANCORP, INC. |
| Entity Incorporation, State or Country Code | MT |
| Entity File Number | 000-18911 |
| Entity Tax Identification Number | 81-0519541 |
| Entity Address, Address Line One | 49 Commons Loop |
| Entity Address, City or Town | Kalispell, |
| Entity Address, State or Province | MT |
| Entity Address, Postal Zip Code | 59901 |
| City Area Code | (406) |
| Local Phone Number | 756-4200 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, $0.01 par value |
| Trading Symbol | GBCI |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0000868671 |
| Amendment Flag | false |
