Note Q — Supplemental Executive Retirement Plans

Defined Benefit Supplemental Executive Retirement Plan

Effective January 2004, we implemented an unfunded noncontributory defined benefit plan (“DB SERP”) for certain senior executives. The DB SERP, which we administer, calls for fifteen annual payments upon retirement with the payment amount based on years of service and final average salary. Benefit costs and liability balances are calculated based on certain assumptions including benefits earned, discount rates, interest costs, mortality rates, and other factors. Actual results that differ from the assumptions are accumulated and amortized over future periods, affecting the recorded obligation and expense in future periods.

We believe the assumptions used are appropriate; however, changes in assumptions or differences in actual experience may affect our benefit obligation and future expenses. The DB SERP's change in net benefit cost and obligation during the three and six months ended June 30, 2019 and 2018 is as follows:

Change in Benefit Obligation:


(in thousands)	2019		2018
Benefit obligation as of March 31	$	17,299	$	19,158
Service cost		84		92
Interest cost		164		150
Payments		(12)		(12)
Benefit obligation as of June 30	$	17,535	$	19,388

Benefit obligation as of December 31, 2018 and 2017, respectively	$	18,927	$	20,793
Service cost		168		184
Interest cost		329		300
Payments		(1,889)		(1,889)
Benefit obligation as of June 30	$	17,535	$	19,388

Amounts Recognized in the Condensed Consolidated Balance Sheets:


	As of June 30,		As of December 31,
(in thousands)	2019		2018
Accrued expenses and other current liabilities	$	1,913	$	1,913
Other liabilities		15,622		17,014
Total accrued liabilities	$	17,535	$	18,927

Defined Contribution Supplemental Executive Retirement Plan

In 2013, we established a defined contribution plan (“DC SERP”) that covers certain of our senior executives. Each participant is given a notional account to manage his or her annual distributions and allocate the funds among various investment options (e.g. mutual funds). These accounts are tracking accounts only for the purpose of calculating the participant’s benefit. The participant does not have ownership of the underlying mutual funds. When a participant initiates or changes the allocation of his or her notional account, we will generally make an allocation of our investments to match those chosen by the participant. While the allocation of our sub accounts is generally intended to mirror the participant’s account records (i.e. the distributions and gains or losses on those funds), the employee does not have legal ownership of any funds until payout upon retirement. The underlying investments are owned by the insurance company with which we own an insurance policy.

As of June 30, 2019 and December 31, 2018, the estimated accumulated obligation benefit is $3.2 million and $3.0 million, respectively, of which $2.9 million and $2.4 million is funded and $0.3 million and $0.6 million is unfunded at June 30, 2019 and December 31, 2018, respectively.

In connection with the DC SERP benefit obligation, we maintain a company-owned life insurance policy (“COLI”). The carrying value of the COLI is measured at its cash surrender value and is presented within “Other assets” in our consolidated balance sheets. See Note I - “Other Current Assets and Other Assets” for additional information.