As the Company generates cash from operations, it is invested in accordance with the Company’s investment policy and corporate goals. The Company’s investment policy has been designed to balance multiple goals, including the assurance of a stable source of income from interest and dividends, the preservation of principal, and the provision of liquidity sufficient to meet insurance underwriting and other obligations as they become payable in the future. Securities purchased may include a combination of taxable or tax-exempt fixed maturity securities and equity securities. The Company also invests in short-term investments that include commercial paper and money-market funds. The Company strives to maintain a high quality investment portfolio. Interest and investment income levels are primarily a function of general market performance, interest rates and the amount of cash available for investment.
As discussed in Note 1 to the consolidated financial statements, the Company changed its method of accounting for certain equity investments as of January 1, 2018 due to the adoption of ASU No. 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities.
Principles of Consolidation and Basis of Presentation: The accompanying Consolidated Financial Statements include the accounts and operations of Investors Title Company and its subsidiaries, and have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”). Earnings attributable to noncontrolling interests in majority-owned insurance agencies are recorded in the Consolidated Statements of Income. Noncontrolling interests representing the portion of equity not related to the Company's ownership interests are recorded in separate sections of the Consolidated Balance Sheets. All intercompany balances and transactions have been eliminated in consolidation.
The Company’s accumulated other comprehensive income is comprised of unrealized holding gains/losses on available-for-sale securities, net of tax, and unrecognized prior service cost and unrealized gains/losses associated with postretirement benefit liabilities, net of tax. Accumulated other comprehensive income as of December 31, 2018 consists of $981 thousand of unrealized holding gains on available-for-sale securities and $32 thousand of unrecognized actuarial losses associated with postretirement benefit liabilities. Accumulated other comprehensive income as of December 31, 2017 consists of $16.0 million of unrealized holding gains on available-for-sale securities and $58 thousand of unrecognized actuarial losses associated with postretirement benefit liabilities. Accumulated other comprehensive income as of December 31, 2016 consists of $11.9 million of unrealized holding gains on available-for-sale securities and $110 thousand of unrecognized actuarial losses associated with postretirement benefit liabilities.
In January 2017, the FASB issued ASU 2017-04, Intangibles - Goodwill and Other (Topic 350). This update removes the requirement to compare the implied fair value of goodwill with its carrying amount as part of step 2 of the goodwill impairment test. As a result, under the ASU, an entity should perform its annual, or interim, goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount and should recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value; however, the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. In addition, the ASU clarifies that an entity should consider income tax effects from any tax deductible goodwill on the carrying amount of the reporting unit when measuring the goodwill impairment loss, if applicable. The update is effective for annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2019. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. None of these amendments are expected to have a material impact on the Company's financial position or results of operations.
The Company continually refines its reserve estimates as current loss experience develops and credible data emerges. Movements in the reserve related to prior periods were primarily the result of changes to estimates to better reflect the latest reported loss data. The 2018 decrease in the provision for claims compared with 2017 primarily related to favorable loss experience and higher levels of favorable loss development in 2018. The favorable development in 2018 was primarily related to policy years 2011 through 2017. Due to variances between actual and expected loss payments, loss development is subject to significant variability.
The Company leases certain office facilities and equipment under operating leases. Rental expense also includes occasional rental of automobiles. Rent expense totaled approximately $1.4 million, $1.2 million, and $896 thousand in 2018, 2017 and 2016, respectively. The future minimum lease payments under operating leases that have initial or remaining noncancelable lease terms in excess of one year as of December 31, 2018, are summarized as follows:
Development of the accumulated postretirement benefit obligation for the years ended December 31, 2018 and 2017 includes the following: