This authoritative guidance clarifies the definition of a business to assist with evaluating when transactions involving an integrated set of assets and activities (a "set") should be accounted for as acquisitions or disposals of assets or businesses. The guidance requires that when substantially all of the fair value of the gross assets acquired or disposed of is concentrated in a single identifiable asset or a group of similar identifiable assets, the set is not a business. The guidance also requires a set to include, at a minimum, an input and a substantive process that together significantly contribute to the ability to create output to be considered a business. Lastly, the guidance removes the evaluation of whether a market participant could replace missing elements and narrows the definition of outputs by more closely aligning it with how outputs are described in the revenue recognition guidance. The guidance will be applied prospectively.
The guidance will be adopted using the modified retrospective application. Only a portion of our total revenues, less than 20%, are subject to this guidance as it does not apply to revenue on contracts accounted for under the insurance contracts or financial instruments standards. Our evaluation process is complete and included, but was not limited to, identifying contracts within the scope of the guidance, reviewing and documenting our accounting for these contracts, identifying and determining the accounting for any related contract costs, and preparing the required financial statement disclosures. While we did not identify material changes in the timing of our revenue recognition, we will have financial statement changes related to contract costs. We will defer certain sales compensation related to obtaining contracts with customers that we did not previously defer, we will no longer defer certain contract costs that were previously capitalized and we will change how we amortize certain contract costs that were previously capitalized, which will result in a net reduction to the contract cost balance. These financial statement changes are not material and result in an immaterial reduction to equity.
Hedge Documentation and Effectiveness Testing. At inception, we formally document all relationships between hedging instruments and hedged items, as well as our risk management objective and strategy for undertaking various hedge transactions. This process includes associating all derivatives designated as fair value or cash flow hedges with specific assets or liabilities on the consolidated statements of financial position or with specific firm commitments or forecasted transactions. Effectiveness of the hedge is formally assessed at inception and throughout the life of the hedging relationship. Even if a derivative is highly effective and qualifies for hedge accounting treatment, the hedge might have some ineffectiveness.
We invest in several real estate limited partnerships and limited liability companies. The entities invest in real estate properties. Certain of these entities are VIEs based on the combination of our significant economic interest and related voting rights. We determined we are the primary beneficiary as a result of our power to control the entities through our significant ownership. Due to the nature of these real estate investments, the investment balance will fluctuate as we purchase and sell interests in the entities and as capital expenditures are made to improve the underlying real estate.
We estimate the amount of the credit loss component of a fixed maturity security impairment as the difference between amortized cost and the present value of the expected cash flows of the security. The present value is determined using the best estimate cash flows discounted at the effective interest rate implicit to the security at the date of purchase or the current yield to accrete an asset-backed or floating rate security. The methodology and assumptions for establishing the best estimate cash flows vary depending on the type of security. The ABS cash flow estimates are based on security specific facts and circumstances that may include collateral characteristics, expectations of delinquency and default rates, loss severity and prepayment speeds and structural support, including subordination and guarantees. The corporate security cash flow estimates are derived from scenario-based outcomes of expected corporate restructurings or liquidations using bond specific facts and circumstances including timing, security interests and loss severity.
Of the total amounts, Principal Life's consolidated portfolio represented $16,918.9 million in available-for-sale fixed maturities with gross unrealized losses of $615.1 million. Of the available-for-sale fixed maturities within Principal Life's consolidated portfolio in a gross unrealized loss position, 94% were investment grade (rated AAA through BBB-) with an average price of 96 (carrying value/amortized cost) as of December 31, 2016. Gross unrealized losses in our fixed maturities portfolio decreased during the year ended December 31, 2016, primarily due to tightening of credit spreads partially offset by an increase in interest rates.
The amortized cost of our commercial mortgage loan portfolio by credit risk, as determined by our internal rating system expressed in terms of an S&P bond equivalent rating, was as follows:
The financial instruments that are subject to master netting agreements or similar agreements include right of setoff provisions. Derivative instruments include provisions to setoff positions covered under the agreements with the same counterparties and provisions to setoff positions outside of the agreements with the same counterparties in the event of default by one of the parties. Derivative instruments also include collateral or variation margin provisions, which are generally settled daily with each counterparty. See Note 5, Derivative Financial Instruments, for further details.
We have defined benefit pension plans covering substantially all of our U.S. employees and certain agents. Some of these plans provide supplemental pension benefits to employees and agents with salaries and/or pension benefits in excess of the qualified plan limits imposed by U.S. federal tax law. The employees and agents are generally first eligible for the pension plans when they reach age 21. For plan participants employed prior to January 1, 2002, the pension benefits are based on the greater of a final average pay benefit or a cash balance benefit. The final average pay benefit is based on the years of service and generally the employee's or agent's average annual compensation during the last five years of employment. Partial benefit accrual of final average pay benefits is recognized from first eligibility until retirement based on attained service divided by potential service to age 65 with a minimum of 35 years of potential service. The cash balance portion of the plan started on January 1, 2002. An employee's account is credited with an amount based on the employee's salary, age and service. These credits accrue with interest. For plan participants hired on and after January 1, 2002, only the cash balance plan applies. Our policy is to fund the cost of providing pension benefits in the years that the employees and agents are providing service to us. Our funding policy for the qualified defined benefit plan is to contribute an amount annually at least equal to the minimum annual contribution required under the Employee Retirement Income Security Act ("ERISA"), and, generally, not greater than the maximum amount that can be deducted for U.S. federal income tax purposes. Our funding policy for the nonqualified benefit plan is to fund the plan in the years the employees are providing service, taking into account the funded status of the trust. While we designate assets to cover the computed liability of the nonqualified plan, the assets are not included as part of the asset balances presented in this footnote as they do not qualify as plan assets in accordance with U.S. GAAP.
Our pension plan assets consist of investments in pooled separate accounts and single client separate accounts. Net asset value ("NAV") of the pooled separate accounts is calculated in a manner consistent with U.S. GAAP for investment companies and is determinative of their fair value. Several of the pooled separate accounts invest in publicly quoted mutual funds or actively managed stocks. The fair value of the underlying mutual funds or stocks is used to determine the NAV of the separate account, which is not publicly quoted. Some of the pooled separate accounts also invest in fixed income securities. The fair value of the underlying securities is based on quoted prices of similar assets and used to determine the NAV of the separate account. Some of the pooled separate accounts invest in real estate properties. The fair value is based on discounted cash flow valuation models that utilize public real estate market data inputs such as transaction prices, market rent growth, vacancy levels, leasing absorption, market capitalization rates and discount rates.
As of December 31, 2017 and 2016, respectively, $93.2 million and $81.8 million of assets, respectively, in cash, fixed income security portfolios, U.S. equity portfolios and international equity portfolios were included in a trust owned life insurance contract.
(4)This input is based on an appropriate industry mortality table and a range does not provide a meaningful presentation.
(1)The 2017 tax benefit includes $568.3 million associated with the U.S. tax reform.
The following is a summary of weighted-average remaining contractual lives for stock options outstanding and the range of exercise prices on the stock options as of December 31, 2017: