Commitments, Contingencies and Guarantees

12 Months Ended

Dec. 31, 2017

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies Disclosure

Commitments, Contingencies and Guarantees

Leases: Minimum rental commitments and minimum royalty requirements under all noncancellable operating leases, primarily quarry property, in effect at December 31, 2017 were (in thousands):

Years Ending December 31,
2018	$	12,169
2019	8,946
2020	7,997
2021	6,874
2022	4,794
Later years (through 2046)	7,171
Total	$	47,951

Operating lease and equipment rental and royalty expense primarily included in cost of revenue in our consolidated statements of operations was $16.4 million, $18.2 million and $11.3 million in 2017, 2016 and 2015, respectively. 

Performance Guarantees

We participate in various joint ventures and line item joint ventures under which each partner is responsible for performing certain discrete items of the total scope of contracted work. See Note 1, Note 6 and Note 10 for further details.

Surety Bonds

We are generally required to provide various types of surety bonds that provide an additional measure of security under certain public and private sector contracts. At December 31, 2017, $3.5 billion of our contract backlog was bonded. Performance bonds do not have stated expiration dates; rather, we are generally released from the bonds after the owner accepts the work performed under contract. The ability to maintain bonding capacity to support our current and future level of contracting requires that we maintain cash and working capital balances satisfactory to our sureties.