PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS

6 Months Ended

Sep. 30, 2011

Compensation and Retirement Disclosure [Abstract]

PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS

PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS

The Company sponsors several defined benefit pension plans covering some of its employees. Certain employee groups are ineligible to participate in the plans or have ceased to accrue additional benefits under the plans based upon their service to the Company or years of service accrued under the defined benefit pension plans. Benefits under the defined benefit plans are based on years of service and, for most non-represented employees, on average compensation for certain years. It is the Company’s policy to fund at least the minimum amount required for all qualified plans, using actuarial cost methods and assumptions acceptable under U.S. Government regulations, by making payments into a separate trust.

In addition to the defined benefit pension plans, the Company provides certain healthcare and life insurance benefits for eligible retired employees. Such benefits are unfunded. Employees achieve eligibility to participate in these contributory plans upon retirement from active service if they meet specified age and years of service requirements. Election to participate for some employees must be made at the date of retirement. Qualifying dependents at the date of retirement are also eligible for medical coverage. Current plan documents reserve the right to amend or terminate the plans at any time, subject to applicable collective bargaining requirements for represented employees. From time to time, changes have been made to the benefits provided to various groups of plan participants. Premiums charged to most retirees for medical coverage prior to age 65 are based on years of service and are adjusted annually for changes in the cost of the plans as determined by an independent actuary. In addition to this medical inflation cost-sharing feature, the plans also have provisions for deductibles, co-payments, coinsurance percentages, out-of-pocket limits, schedules of reasonable fees, preferred provider networks, coordination of benefits with other plans and a Medicare carve-out.

In accordance with the Compensation – Retirement Benefits topic of the ASC, the Company has recognized the funded status of the benefit obligation as of the date of the last remeasurement, in the accompanying consolidated balance sheet. The funded status is measured as the difference between the fair value of the plan’s assets and the PBO or accumulated postretirement benefit obligation of the plan. In order to recognize the funded status, the Company determined the fair value of the plan assets. The majority of the plan assets are publicly traded investments which were valued based on the market price as of the date of remeasurement. Investments that are not publicly traded were valued based on the estimated fair value of those investments based on our evaluation of data from fund managers and comparable market data.

Net Periodic Benefit Plan Costs

The components of net periodic benefit costs for our postretirement benefit plans are shown in the following table:

	Pension benefits
	Three Months Ended September 30,						Six Months Ended September 30,
	2011			2010			2011			2010
Components of net periodic benefit expense (income):
Service cost	$	4,114		$	5,151		$	8,228		$	6,026
Interest cost	27,014			29,237			54,029			34,260
Expected return on plan assets	(31,900		)	(29,281		)	(63,801		)	(34,283		)
Amortization of prior service costs	(2,754		)	18			(5,507		)	36
Amortization of net loss	28			46			57			92
Net periodic benefit expense (income)	$	(3,498	)	$	5,171		$	(6,994	)	$	6,131

	Other post-retirement benefits
	Three Months Ended September 30,					Six Months Ended September 30,
	2011			2010		2011			2010
Components of net periodic benefit expense:
Service cost	$	849		$	990	$	1,697		$	1,155
Interest cost	4,619			5,326		9,237			6,214
Amortization of prior service costs	(1,133		)	—		(2,265		)	—
Net periodic benefit expense	$	4,335		$	6,316	$	8,669		$	7,369