Notes to Consolidated Financial Statements 48 and current economic and business conditions. Management believes that as of December 31, 2004, no significant concentrations of credit risk existed for which an allowance had not already been recorded. Inventories. Inventories consist of food and beverage, retail merchandise and  operating supplies, and are stated at the lower of cost or market. Cost is determined primarily by the average cost method for food and beverage and supplies and the retail inventory or specific identification methods for retail merchandise. Property and equipment.  Property and equipment are stated at cost. Gains or loss- es on dispositions of property and equipment are included in the determination of income. Maintenance costs are expensed as incurred. Property and equipment are generally depreciated over the following estimated useful lives on a straight-line basis: We evaluate our property and equipment and other long-lived assets for impairment in accordance with the Financial Accounting Standards Board’s Statement of Financial Accounting Standards No. 144, “Accounting for the Impairment or Disposal of Long-Lived Assets.” For assets to be disposed of, we recognize the asset to be sold at the lower of carrying value or fair value less costs of disposal. Fair value for assets to be disposed of is estimated based on comparable asset sales, solicited offers, or a discounted cash flow model. For assets to be held and used, we review fixed assets for impairment whenever  indicators of impairment exist. If an indicator of impairment exists, we compare the estimated future cash flows of the asset, on an undiscounted basis, to the carrying value of the asset. If the undiscounted cash flows exceed the carrying value, no impairment is indicated. If the undiscounted cash flows do not exceed the carrying value, then an impairment is measured based on fair value compared to carrying value, with fair value typically based on a discounted cash flow model. If an asset is still under development, future cash flows include remaining construction costs. For a discussion of recognized impairment losses, see Note 14. In October 2002, the Company announced the suspension of development activities on its wholly- owned project on the Renaissance Pointe land in Atlantic City. In connection  therewith, the Company reviewed the land for potential impairment, and deter- mined that no impairment was indicated. In December 2002, the Company entered into an agreement with Turnberry Associates to form a venture to construct condominium residences behind MGM Grand Las Vegas. As part of the agreement, the Company contributed land to the venture. The Company reviewed the land for potential impairment, and determined no impairment was indicated.  Capitalized interest.  The interest cost associated with major development and  construction projects is capitalized and included in the cost of the project. When  no debt is incurred specifically for a project, interest is capitalized on amounts expended on the project using the weighted-average cost of the Company’s  outstanding borrowings. Capitalization of interest ceases when the project is  substantially complete or development activity is suspended for more than a  brief period. Buildings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 years Building improvements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 to 40 years Land improvements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15  to 40 years Equipment, furniture, fixtures, and leasehold improvements . . . . . . . . . . . . . . . . 3 to 20 years