Commitments and Contingencies	3 Months Ended
Mar. 31, 2018
Commitments and Contingencies.
Commitments and Contingencies	8. Commitments and Contingencies Litigation We are involved from time-to-time in various legal and regulatory proceedings that arise in the ordinary course of our business, including, but not limited to, commercial disputes, environmental matters, and litigation in connection with transactions such as acquisitions and divestitures. We believe that current proceedings will not have a material adverse effect on our financial condition, liquidity, or results of operations. We record a liability when a loss is considered probable and the amount can be reasonably estimated. In May 2010, Opry Mills sustained significant flood damage. Insurance proceeds of $50 million have been funded by the primary insurer and remediation and restoration work has been completed. The property re‑opened on March 29, 2012. The excess insurance carriers (those providing coverage above $50 million) denied our claim under the policy for additional proceeds (of up to $150 million) to pay further amounts for restoration costs and business interruption losses. In the first quarter of 2015, summary judgment was granted by the trial court in our favor, concluding that up to $150 million of additional coverage is available under our excess insurance policies for this claim. In July and August 2015, trial on the damages portion of our claim was completed and the jury entered a verdict for damages in the amount of $204.1 million (inclusive of the $50.0 million previously paid by the primary carrier). In April 2016, the court entered final judgment in the amount of the jury verdict. On January 26, 2018, the Court of Appeals of Tennessee reversed the trial court’s summary judgment on the amount of available coverage and ruled that the policy limit was $50 million. The Company is seeking a review of this ruling by the Tennessee Supreme Court. We will continue our efforts through the conclusion of the pending litigation, including any and all appeals, to recover our losses, including consequential damages, under the excess insurance policies for Opry Mills and from our former insurance broker, Aon Risk Services Central Inc., who is a defendant in this case, but did not participate in the trial. However, no assurance can be made that our efforts to recover these losses will be successful. Guarantees of Indebtedness Joint venture debt is the liability of the joint venture and is typically secured by the joint venture property, which is non-recourse to us. As of March 31, 2018 and December 31, 2017, the Operating Partnership guaranteed joint venture related mortgage indebtedness of $207.0 million and $211.6 million, respectively (of which we have a right of recovery from our venture partners of $10.8 million). Mortgages guaranteed by the Operating Partnership are secured by the property of the joint venture which could be sold in order to satisfy the outstanding obligation and which has an estimated fair value in excess of the guaranteed amount. Concentration of Credit Risk Our U.S. Malls, Premium Outlets, and The Mills rely heavily upon anchor tenants to attract customers; however, anchor retailers do not contribute materially to our financial results as many anchor retailers own their spaces. All material operations are within the United States and no customer or tenant accounts for 5% or more of our consolidated revenues.

8. Commitments and Contingencies

Litigation

We are involved from time-to-time in various legal and regulatory proceedings that arise in the ordinary course of our business, including, but not limited to, commercial disputes, environmental matters, and litigation in connection with transactions such as acquisitions and divestitures. We believe that current proceedings will not have a material adverse effect on our financial condition, liquidity, or results of operations. We record a liability when a loss is considered probable and the amount can be reasonably estimated.

In May 2010, Opry Mills sustained significant flood damage. Insurance proceeds of $50 million have been funded by the primary insurer and remediation and restoration work has been completed. The property re‑opened on March 29, 2012. The excess insurance carriers (those providing coverage above $50 million) denied our claim under the policy for additional proceeds (of up to $150 million) to pay further amounts for restoration costs and business interruption losses. In the first quarter of 2015, summary judgment was granted by the trial court in our favor, concluding that up to $150 million of additional coverage is available under our excess insurance policies for this claim. In July and August 2015, trial on the damages portion of our claim was completed and the jury entered a verdict for damages in the amount of $204.1 million (inclusive of the $50.0 million previously paid by the primary carrier). In April 2016, the court entered final judgment in the amount of the jury verdict. On January 26, 2018, the Court of Appeals of Tennessee reversed the trial court’s summary judgment on the amount of available coverage and ruled that the policy limit was $50 million. The Company is seeking a review of this ruling by the Tennessee Supreme Court. We will continue our efforts through the conclusion of the pending litigation, including any and all appeals, to recover our losses, including consequential damages, under the excess insurance policies for Opry Mills and from our former insurance broker, Aon Risk Services Central Inc., who is a defendant in this case, but did not participate in the trial. However, no assurance can be made that our efforts to recover these losses will be successful.

Guarantees of Indebtedness

Joint venture debt is the liability of the joint venture and is typically secured by the joint venture property, which is non-recourse to us. As of March 31, 2018 and December 31, 2017, the Operating Partnership guaranteed joint venture related mortgage indebtedness of $207.0 million and $211.6 million, respectively (of which we have a right of recovery from our venture partners of $10.8 million). Mortgages guaranteed by the Operating Partnership are secured by the property of the joint venture which could be sold in order to satisfy the outstanding obligation and which has an estimated fair value in excess of the guaranteed amount.

Concentration of Credit Risk

Our U.S. Malls, Premium Outlets, and The Mills rely heavily upon anchor tenants to attract customers; however, anchor retailers do not contribute materially to our financial results as many anchor retailers own their spaces. All material operations are within the United States and no customer or tenant accounts for 5% or more of our consolidated revenues.