10.	Employee Benefit Plans and Other Postretirement Benefits

PCA has defined pension benefit plans for both salaried and hourly employees. The plans covering salaried employees are closed to new entrants with only certain current active participants still accruing benefits. The plans covering certain hourly employees are closed to new participants. We also have a Supplemental Executive Retirement Plan (SERP) and other nonqualified defined benefit pension plans that provide unfunded supplemental retirement benefits to certain of our executives and former executives. The SERP provides for incremental pension benefits in excess of those offered in our principal pension plans.

Other Postretirement Benefits

PCA provides postretirement medical benefits for certain salaried employees and postretirement medical and life insurance benefits for certain hourly employees. For salaried employees, the plan covers employees retiring from PCA on or after attaining age 58 who have had at least 10 years of full-time service with PCA after attaining age 48. In April 2016, the Company provided notice to eligible participants that the Salaried Retiree Medical Plan would be frozen as of December 31, 2016. As a result of the freeze, eligible plan participants who did not retire and elect coverage before December 31, 2016 would lose benefits attributable to service already rendered. In accordance with Accounting Standards Codification (ASC) 715, “Compensation--Retirement Benefits”, the Company remeasured the Salaried Retiree Medical Plan benefit obligation using current assumptions, resulting in a decrease in the benefit obligation of $5.1 million with a corresponding increase in accumulated other comprehensive income of $3.1 million and deferred income taxes of $2.0 million.

Obligations and Funded Status of Defined Benefit Pension and Other Postretirement Benefits Plans

The funded status of PCA's plans change from year to year based on the plan asset investment return, contributions, benefit payments, the discount rate used to measure the liability, and expected participant longevity. The following table, which includes only company-sponsored defined benefit and other postretirement benefit plans, reconciles the beginning and ending balances of the projected benefit obligation and the fair value of plan assets. We recognize the unfunded status of these plans on the Consolidated Balance Sheets, and we recognize changes in funded status in the year changes occur through the Consolidated Statements of Comprehensive Income (dollars in millions):

	Pension Plans						Postretirement Plans
	Year Ended December 31						Year Ended December 31
	2017			2016			2017			2016
Change in Benefit Obligation
Benefit obligation at beginning of period	$	1,158.4		$	1,092.5		$	19.5		$	21.4
Service cost		23.7			24.5			0.3			0.5
Interest cost		41.6			40.9			0.6			0.6
Plan amendments		17.3			1.8			(0.5	)		(5.3	)
Actuarial loss (gain) (a)		99.3			35.3			(2.2	)		3.7
Participant contributions		—			—			1.3			1.3
Benefits paid		(40.1	)		(36.6	)		(2.5	)		(2.7	)
Benefit obligation at plan year end	$	1,300.2		$	1,158.4		$	16.5		$	19.5
Accumulated benefit obligation portion of above	$	1,237.7		$	1,116.6
Change in Fair Value of Plan Assets
Plan assets at fair value at beginning of period	$	830.4		$	764.4		$	—		$	—
Actual return on plan assets		121.0			44.4			—			—
Company contributions		43.5			58.2			1.2			1.4
Participant contributions		—			—			1.3			1.3
Benefits paid		(40.1	)		(36.6	)		(2.5	)		(2.7	)
Fair value of plan assets at plan year end	$	954.8		$	830.4		$	—		$	—
Underfunded status	$	(345.4	)	$	(328.0	)	$	(16.5	)	$	(19.5	)
Amounts Recognized on Consolidated Balance Sheets
Current liabilities	$	(1.4	)	$	(1.3	)	$	(1.0	)	$	(1.2	)
Noncurrent liabilities		(344.0	)		(326.7	)		(15.5	)		(18.3	)
Accrued obligation recognized at December 31	$	(345.4	)	$	(328.0	)	$	(16.5	)	$	(19.5	)
Amounts Recognized in Accumulated Other Comprehensive Loss (Income) (Pre-Tax)
Prior service cost (credit)	$	32.7		$	21.1		$	(5.3	)	$	(5.0	)
Actuarial loss (gain)		208.5			183.9			(4.0	)		(1.9	)
Total	$	241.2		$	205.0		$	(9.3	)	$	(6.9	)

(a)

The actuarial loss in 2017 was due primarily to a decrease in the weighted average discount rate used to estimate our pension benefit obligations. In 2016, a decrease in the weighted average discount rate used to estimate our pension benefit obligations and changes in mortality assumptions from the Society of Actuaries resulted in an actuarial loss.

Components of Net Periodic Benefit Cost and Other Comprehensive (Income) Loss

The components of net periodic benefit cost and other comprehensive (income) loss (pretax) were as follows (dollars in millions):

	Pension Plans									Postretirement Plans
	Year Ended December 31									Year Ended December 31
	2017			2016			2015			2017			2016			2015
Service cost	$	23.7		$	24.5		$	24.0		$	0.3		$	0.5		$	1.7
Interest cost		41.6			40.9			46.2			0.6			0.6			1.2
Expected return on plan assets		(53.9	)		(49.5	)		(53.1	)		—			—			—
Net amortization of unrecognized amounts
Prior service cost (credit)		5.8			5.7			5.5			(0.2	)		(0.1	)		0.1
Actuarial loss (gain)		7.6			5.8			8.7			(0.1	)		(0.4	)		0.1
Net periodic benefit cost	$	24.8		$	27.4		$	31.3		$	0.6		$	0.6		$	3.1
Changes in plan assets and benefit obligations recognized in other comprehensive (income) loss
Actuarial net loss (gain)	$	32.2		$	40.4		$	(14.5	)	$	(2.2	)	$	3.6		$	(11.4	)
Prior service cost (credit)		17.4			1.8			3.0			(0.6	)		(5.3	)		—
Amortization of prior service cost (credit)		(5.8	)		(5.7	)		(5.5	)		0.2			(0.3	)		(0.1	)
Amortization of actuarial loss (gain)		(7.6	)		(5.8	)		(8.7	)		0.1			0.8			(0.1	)
Total recognized in other comprehensive loss (income) (a)	$	36.2		$	30.7		$	(25.7	)	$	(2.5	)	$	(1.2	)	$	(11.6	)
Total recognized in net periodic benefit cost and other comprehensive loss (income) (pre-tax)	$	61.0		$	58.1		$	5.6		$	(1.9	)	$	(0.6	)	$	(8.5	)

(a)

Accumulated losses in excess of 10% of the greater of the projected benefit obligation or the market-related value of assets will be recognized on a straight-line basis over the average remaining service period of active employees in PCA plans (which is between seven to ten years) and over the average remaining lifetime of inactive participants of Boise plans (which is between 25 and 28 years), to the extent that losses are not offset by gains in subsequent years. The estimated net loss and prior service cost that will be amortized from “Accumulated other comprehensive loss” into net periodic benefit in 2018 is $15.8 million.

The accumulated benefit obligations for the plans with obligations in excess of plan assets, is $1.2 billion.

Assumptions

The following table presents the assumptions used in the measurement of our benefits obligations:

	Pension Plans					Postretirement Plans
	December 31					December 31
	2017	2016		2015		2017	2016	2015
Weighted-Average Assumptions Used to Determine Benefit Obligations at December 31
Discount rate	3.66%	4.24%		4.51%		3.55%	3.91%	4.35%
Rate of compensation increase	4.00%		4.00%		4.00%	N/A	N/A	N/A
Weighted-Average Assumptions Used to Determine Net Periodic Benefit Cost for the Years Ended December 31
Discount rate	4.24%	4.49%		4.14%		3.92%	4.17%	3.95%
Expected return on plan assets	6.55%	6.57%		6.73%		N/A	N/A	N/A
Rate of compensation increase	4.00%		4.00%		4.00%	N/A	N/A	N/A

Discount Rate Assumption. The discount rate reflects the current rate at which the pension obligations could be settled on the measurement date: December 31. The discount rate assumption used to calculate the present value of pension and postretirement benefit obligations reflects the rates available on high-quality, fixed-income debt instruments on December 31. In all periods, the bonds included in the models reflect anticipated investments that would be made to match the expected monthly benefit payments over time. The plans' projected cash flows were duration-matched to these models to develop an appropriate discount rate.

Beginning in 2016, we refined the method used to determine the service and interest cost components of our net periodic benefit cost. Previously, the cost was determined using a single weighted-average discount rate derived from the yield curve. Under the refined method, known as the spot rate approach, we will use individual spot rates along the yield curve that correspond with the timing of each benefit payment. We believe this change provides a more precise measurement of service and interest costs by improving the correlation between projected cash outflows and corresponding spot rates on the yield curve.

Asset Return Assumption. The expected return on plan assets reflects the expected long-term rates of return for the categories of investments currently held in the plans as well as anticipated returns for additional contributions made in the future. The expected long-term rate of return is adjusted when there are fundamental changes in expected returns on the plan investments. The weighted-average expected return on plan assets we will use in our calculation of 2018 net periodic pension benefit cost is 6.06%.

Rate of Compensation Increase. The rate of compensation increase is determined by PCA based upon annual reviews. The compensation increase assumption is not applicable for all plans as many of our pension plans are frozen and not accruing benefits.

Health Care Cost Trend Rate Assumptions. PCA assumed health care cost trend rates for its postretirement benefits plans were as follows:

	2017	2016	2015
Health care cost trend rate assumed for next year	7.57%	7.35%	7.60%
Rate to which the cost trend rate is assumed to decline (the ultimate trend rate)	4.44%	4.50%	4.50%
Year that the rate reaches the ultimate trend rate	2027	2025	2024

Postretirement Health Care Plan Assumptions. For postretirement health care plan accounting, PCA reviews external data and its own historical trends for health care costs to determine the health care cost trend rate assumption.

A one-percentage point change in assumed health care cost trend rates would have the following effects on the 2017 postretirement benefit obligation and the 2016 net post retirement benefit cost (dollars in millions):


	1-Percentage Point Increase		1-Percentage Point Decrease
Effect on postretirement benefit obligation	$	0.6	$	(0.6	)
Effect on net postretirement benefit cost		0.1		—

Investment Policies and Strategies

PCA has retained the services of professional advisors to oversee pension investments and provide recommendations regarding investment strategy. PCA’s overall strategy and related apportionments between equity and debt securities may change from time to time based on market conditions, external economic factors, and the funded status of the plans. The general investment objective for all of our plan assets is to optimize growth of the pension plan trust assets, while minimizing the risk of significant losses to enable the plans to satisfy their benefit payment obligations over time. The objectives take into account the long-term nature of the benefit obligations, the liquidity needs of the plans, and the expected risk/return trade-offs of the asset classes in which the plans may choose to invest. Assets of our pension plans were invested in the following classes of securities at December 31, 2017 and 2016:

	Percentage of Fair Value at December 31,
	2017			2016
Fixed income securities		21	%		54	%
International equity securities		6	%		23	%
Domestic equity securities		9	%		21	%
Real estate securities		—			1	%
Other		64	%		1	%

As of December 31, 2017, the Company was in the process of consolidating the Boise pension plan assets with the PCA pension plans under one trustee. Due to this timing, 100% of the Boise pension plan assets were classified as Other (Cash) on December 31, 2017. Upon completion of the transfer on January 5, 2018, the pension plan assets were invested in the following classes of securities:

	Percentage of Fair Value at January 5, 2018
Fixed income securities		52	%
International equity securities		28	%
Domestic equity securities		20	%

At December 31, 2017, the targeted investment allocations differed between the acquired Boise plans and PCA's historical plans based on funded status. At December 31, 2017, PCA's historical plans, which comprised $403.5 million of the fair value of plan assets, targeted 50% invested in equities, 49% invested in fixed income securities, and 1% in other, whereas the Boise plans, which comprised $551.3 million of the total fair value of plan assets, targeted 54% invested in fixed income securities, 44% invested in equities, and 2% in other. Our retirement committee reviews the investment allocations for reasonableness at a minimum, semi-annually.

Investment securities, in general, are exposed to various risks, such as interest rate, credit, and overall market volatility risk, all of which are subject to change. Due to the level of risk associated with some investment securities, it is reasonably possible that changes in the values of investment securities will occur in the near term, and such changes could materially affect the reported amounts.

Fair Value Measurements of Plan Assets

The following tables set forth, by level within the fair value hierarchy, discussed in Note 2, Summary of Significant Accounting Policies, the pension plan assets, by major asset category, at fair value at December 31, 2017 and 2016 (dollars in millions):

	Fair Value Measurements at December 31, 2017
Asset Category	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Cash and short-term investments (a)	$	602.4	$	5.7	$	—	$	608.1
Mutual funds:
International equities		56.1		—		—		56.1
Fixed income		95.4		—		—		95.4
Common/collective trust funds (b):
Domestic equities		—		84.1		—		84.1
International equities		—		5.6		—		5.6
Fixed income		—		59.8		—		59.8
Corporate and government bonds:
Fixed income		41.3		—		—		41.3
Private equity securities (c)		—		—		4.2		4.2
Total securities at fair value	$	795.2	$	155.2	$	4.2	$	954.6
Receivables and accrued expenses								0.2
Total fair value of plan assets							$	954.8

	Fair Value Measurements at December 31, 2016
Asset Category	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Cash and short-term investments	$	—	$	1.5	$	—	$	1.5
Mutual funds:
Domestic equities		65.7		—		—		65.7
International equities		68.7		—		—		68.7
Real estate		9.6		—		—		9.6
Fixed income		108.4		64.8		—		173.2
Common/collective trust funds (b):		—
Domestic equities		—		107.9		—		107.9
International equities		—		124.5		—		124.5
Fixed income		—		271.6		—		271.6
Private equity securities (c)		—		—		5.7		5.7
Total securities at fair value	$	252.4	$	570.3	$	5.7	$	828.4
Receivables and accrued expenses								2.0
Total fair value of plan assets							$	830.4

(a)	Short-term investments and the Boise pension plan assets classified as cash as of December 31, 2017. The Boise pension plan assets were subsequently allocated to equities and fixed income securities on January 5, 2018 after consolidating with the PCA pension plan assets under one trustee.

(b)

Investments in common/collective trust funds valued using net asset values (NAV) provided by the administrator of the funds. The NAV is based on the value of the underlying assets owned by the fund, minus its liabilities, and then divided by the number of units outstanding. While the underlying assets are actively traded on an exchange, the funds are not. There are currently no redemption restrictions on these investments. There are certain funds with one-day redeemable notice.

(c)

Investments in this category are invested in the Pantheon Global Secondary Fund IV, LP. The fund specializes in investments in the private equity secondary market and occasionally directly in private companies to maximize capital growth. Fund investments are carried at fair value as determined quarterly using the market approach to estimate the fair value of private investments. The market approach utilizes prices and other relevant information generated by market transactions, type of security, size of the position, degree of liquidity, restrictions on the disposition, latest round of financing data, current financial position, and operating results, among other factors. In circumstances where fair values are not provided with respect to any of the company's fund investments, the investment advisor will seek to determine the fair value of such investments based on information provided by the general partners or managers of such funds or from other sources. Audited financial statements are provided by fund management annually. Notwithstanding the above, the variety of valuation bases adopted and quality of management data of the ultimate underlying investee companies means that there are inherent difficulties in determining the value of the investments. Amounts realized on the sale of these investments may differ from the calculated values. Boise had originally committed to a $15.0 million investment, with $5.0 million of the commitment unfunded at December 31, 2017.

The following table sets forth a summary of changes in the fair value of the pension plans' Level 3 assets for the year ended December 31, 2017 (dollars in millions):

	2017
Balance, beginning of year	$	5.7
Acquisitions		—
Purchases		—
Sales		(1.5	)
Unrealized gain		—
Balance, end of year	$	4.2

Funding and Cash Flows

PCA makes pension plan contributions that are sufficient to fund its actuarially determined costs, generally equal to the minimum amounts required by the Employee Retirement Income Security Act (ERISA). From time to time, PCA may make discretionary contributions based on the funded status of the plans, tax deductibility, income from operations, and other factors. In 2017, we made contributions of $42.1 million to our qualified pension plans. In 2016, we made contributions of $57.1 million to our qualified pension plans. In 2015, we did not make contributions to our qualified pension plans. We expect to contribute at least the estimated required minimum contributions to our qualified pension plans of approximately $4.6 million in 2018.

The following are estimated benefit payments to be paid to current plan participants by year (dollars in millions). Qualified pension benefit payments are paid from plan assets, while nonqualified pension benefit payments are paid by the Company.

	Pension Plans		Postretirement Plans
2018	$	45.4	$	1.0
2019		49.3		1.0
2020		53.2		1.0
2021		57.0		0.9
2022 - 2025		407.9		5.4

Defined Contribution Plans

Some of our employees participate in contributory defined contribution savings plans, available to most of our salaried and hourly employees. The defined contribution plans permit participants to make contributions by salary reduction pursuant to Section 401(k) of the Code. PCA made employer-matching contributions of $42.8 million, $40.4 million, and $37.9 million in 2017, 2016, and 2015, respectively. In 2015, Company matching contributions to certain full-time salaried employees were made in company stock, through our Employee Stock Ownership Plan (ESOP). All other matching contributions were in cash. Beginning in 2016, all company-matching contributions to all employees were made in cash. We expense employer matching contributions and charge dividends on shares held by the ESOP to retained earnings. Shares of company stock held by the ESOP are included in basic shares for earnings-per-share computations. At December 31, 2017 and 2016, the ESOP held 1.8 million and 2.2 million shares of Company stock, respectively.

Certain salaried and hourly employees that are not participating in a PCA sponsored defined benefit pension plan receive a service-related company retirement contribution to their defined contribution plan account in addition to any employer matching contribution. This contribution increases with years of service and ranges from 3% to 5% of base pay. We contributed $22.4 million, $14.9 million, and $12.4 million for this retirement contribution during the years ended December 31, 2017, 2016, and 2015, respectively.

Deferred Compensation Plans

Key managers can elect to participate in a deferred compensation plan. The deferred compensation plan is unfunded; therefore, benefits are paid from our general assets. At December 31, 2017 and 2016, we had $13.6 million and $13.7 million, respectively, of liabilities attributable to participation in our deferred compensation plan on our Consolidated Balance Sheets.