Legal Proceedings	9 Months Ended
Sep. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
Legal Proceedings	Legal Proceedings In the ordinary course of business, we or our joint ventures and affiliates are involved in various legal proceedings alleging, among other things, public liability issues, breach of contract or tortious conduct in connection with the performance of services and/or materials provided. We are also subject to government inquiries and reporting requirements seeking information concerning our compliance with government construction contracting requirements and various laws and regulations. The outcomes of such proceedings and government inquiries cannot be predicted with certainty. Some of the matters in which we or our joint ventures and affiliates are involved may include compensatory, punitive, or other claims or sanctions that, if granted, could require us to pay damages or make other expenditures in amounts that are not probable to be incurred or cannot currently be reasonably estimated. In addition, in some circumstances our government contracts could be terminated or suspended, we could be debarred or incur other administrative penalties or sanctions, or payment of our costs could be disallowed. While any of our pending legal proceedings may be subject to early resolution as a result of our ongoing efforts to settle, whether or when any legal proceeding will be resolved through settlement is neither predictable nor guaranteed. Accordingly, it is possible that future developments in such proceedings and inquiries could require us to (i) adjust existing accruals, or (ii) record new accruals that we did not originally believe to be probable or that could not be reasonably estimated. Such changes could be material to our financial condition, results of operations and/or cash flows in any particular reporting period. In addition to matters that are considered probable for which the loss can be reasonably estimated, we also disclose certain matters where the loss is considered reasonably possible and is reasonably estimable. Liabilities relating to legal proceedings and government inquiries, to the extent that we have concluded such liabilities are probable and the amounts of such liabilities are reasonably estimable, are recorded in our condensed consolidated balance sheets. The aggregate liabilities recorded as of September 30, 2017, December 31, 2016 and September 30, 2016 related to these matters were approximately $1.7 million, $4.3 million and $0.7 million, respectively, and were primarily included in accrued expenses and other current liabilities. The aggregate range of reasonably possible loss amounts in excess of accrued losses recorded for probable loss contingencies, including those related to liquidated damages, could have a material impact on our consolidated financial statements if they become probable and the reasonably estimable amount is determined.

Legal Proceedings

In the ordinary course of business, we or our joint ventures and affiliates are involved in various legal proceedings alleging, among other things, public liability issues, breach of contract or tortious conduct in connection with the performance of services and/or materials provided. We are also subject to government inquiries and reporting requirements seeking information concerning our compliance with government construction contracting requirements and various laws and regulations. The outcomes of such proceedings and government inquiries cannot be predicted with certainty.

Some of the matters in which we or our joint ventures and affiliates are involved may include compensatory, punitive, or other claims or sanctions that, if granted, could require us to pay damages or make other expenditures in amounts that are not probable to be incurred or cannot currently be reasonably estimated. In addition, in some circumstances our government contracts could be terminated or suspended, we could be debarred or incur other administrative penalties or sanctions, or payment of our costs could be disallowed. While any of our pending legal proceedings may be subject to early resolution as a result of our ongoing efforts to settle, whether or when any legal proceeding will be resolved through settlement is neither predictable nor guaranteed.

Accordingly, it is possible that future developments in such proceedings and inquiries could require us to (i) adjust existing accruals, or (ii) record new accruals that we did not originally believe to be probable or that could not be reasonably estimated. Such changes could be material to our financial condition, results of operations and/or cash flows in any particular reporting period. In addition to matters that are considered probable for which the loss can be reasonably estimated, we also disclose certain matters where the loss is considered reasonably possible and is reasonably estimable.

Liabilities relating to legal proceedings and government inquiries, to the extent that we have concluded such liabilities are probable and the amounts of such liabilities are reasonably estimable, are recorded in our condensed consolidated balance sheets. The aggregate liabilities recorded as of September 30, 2017, December 31, 2016 and September 30, 2016 related to these matters were approximately $1.7 million, $4.3 million and $0.7 million, respectively, and were primarily included in accrued expenses and other current liabilities. The aggregate range of reasonably possible loss amounts in excess of accrued losses recorded for probable loss contingencies, including those related to liquidated damages, could have a material impact on our consolidated financial statements if they become probable and the reasonably estimable amount is determined.