Leasing Arrangements - Minimum Contractual Commitments Under Long-Term Operating Leases (Detail) $ in Thousands	Dec. 30, 2017 USD ($)
Leases [Abstract]
2018, Operating Leases	$ 8,627
2019, Operating Leases	7,077
2020, Operating Leases	5,826
2021, Operating Leases	4,650
2022, Operating Leases	2,475
2018, Royalty Agreements	6,450
2019, Royalty Agreements	6,017
2020, Royalty Agreements	5,833
2021, Royalty Agreements	5,550
2022, Royalty Agreements	5,431
Summit Materials, LLC
Leases [Abstract]
2018, Operating Leases	8,627
2019, Operating Leases	7,077
2020, Operating Leases	5,826
2021, Operating Leases	4,650
2022, Operating Leases	2,475
2018, Royalty Agreements	6,450
2019, Royalty Agreements	6,017
2020, Royalty Agreements	5,833
2021, Royalty Agreements	5,550
2022, Royalty Agreements	$ 5,431