Consolidated Balance Sheets - Summit Materials Inc (Parenthetical) - $ / shares |
Dec. 31, 2022 |
Dec. 29, 2022 |
Jan. 01, 2022 |
Jan. 02, 2021 |
Dec. 28, 2019 |
|---|---|---|---|---|---|
| Common Class A | |||||
| Common stock, par value (USD per share) | $ 0.01 | $ 0.01 | |||
| Common stock, shares authorized (in shares) | 1,000,000,000 | 1,000,000,000 | |||
| Common stock, shares issued (in shares) | 118,408,655 | 1,979,214 | 118,705,108 | 116,369,809 | 116,369,809 |
| Common stock, shares outstanding (in shares) | 118,408,655 | 118,705,108 | |||
| Common Class B | |||||
| Common stock, par value (USD per share) | $ 0.01 | $ 0.01 | |||
| Common stock, shares authorized (in shares) | 250,000,000 | 250,000,000 | |||
| Common stock, shares issued (in shares) | 99 | 99 | |||
| Common stock, shares outstanding (in shares) | 99 | 99 |