| Document and Entity Information | Sep. 02, 2021 |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Sep. 2, 2021 |
| Entity Registrant Name | Sunstone Hotel Investors, Inc. |
| Entity Central Index Key | 0001295810 |
| Entity Incorporation, State or Country Code | MD |
| Entity File Number | 001-32319 |
| Entity Tax Identification Number | 20-1296886 |
| Entity Address, Address Line One | 200 Spectrum Center Drive |
| Entity Address, Adress Line Two | 21st Floor |
| Entity Address, City or Town | Irvine |
| Entity Address, State or Province | CA |
| Entity Address, Postal Zip Code | 92618 |
| City Area Code | 949 |
| Local Phone Number | 330-4000 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Common Stock | |
| Title of 12(b) Security | Common Stock, $0.01 par value |
| Trading Symbol | SHO |
| Security Exchange Name | NYSE |
| Series H Cumulative Redeemable Preferred Stock | |
| Title of 12(b) Security | Series H Cumulative Redeemable Preferred Stock, $0.01 par value |
| Trading Symbol | SHO.PRH |
| Security Exchange Name | NYSE |
| Series I Preferred Stock | |
| Title of 12(b) Security | Series I Cumulative Redeemable Preferred Stock, $0.01 par value |
| Trading Symbol | SHO.PRI |
| Security Exchange Name | NYSE |
