Employee benefit plans

6 Months Ended

Jun. 30, 2014

Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract]

Pension and other postretirement benefit plans

Employee benefit plans

The Company has noncontributory defined benefit pension plans and other postretirement benefit plans for certain eligible employees. Components of net periodic benefit cost for the Company's pension and other postretirement benefit plans were as follows:

							Other
							Postretirement
	Pension Benefits						Benefits
Three Months Ended June 30,	2014			2013			2014			2013
	(In thousands)
Components of net periodic benefit cost:
Service cost	$	31		$	37		$	380		$	334
Interest cost	4,405			4,106			924			667
Expected return on assets	(5,484		)	(4,875		)	(1,242		)	(1,065		)
Amortization of prior service cost (credit)	18			18			(348		)	(364		)
Amortization of net actuarial loss	1,121			1,716			6			407
Net periodic benefit cost, including amount capitalized	91			1,002			(280		)	(21		)
Less amount capitalized	73			158			(19		)	61
Net periodic benefit cost (credit)	$	18		$	844		$	(261	)	$	(82	)

							Other
							Postretirement
	Pension Benefits						Benefits
Six Months Ended June 30,	2014			2013			2014			2013
	(In thousands)
Components of net periodic benefit cost:
Service cost	$	64		$	77		$	759		$	838
Interest cost	8,845			8,124			1,782			1,607
Expected return on assets	(10,609		)	(9,958		)	(2,309		)	(2,172		)
Amortization of prior service cost (credit)	36			36			(696		)	(728		)
Amortization of net actuarial loss	2,434			3,580			324			1,078
Net periodic benefit cost, including amount capitalized	770			1,859			(140		)	623
Less amount capitalized	168			268			10			90
Net periodic benefit cost (credit)	$	602		$	1,591		$	(150	)	$	533

In addition to the qualified plan defined pension benefits reflected in the table, the Company has unfunded, nonqualified benefit plans for executive officers and certain key management employees that generally provide for defined benefit payments at age 65 following the employee's retirement or to their beneficiaries upon death for a 15-year period. The Company's net periodic benefit cost for this plan for the three and six months ended June 30, 2014, was $1.6 million and $3.3 million, respectively. The Company's net periodic benefit cost for this plan for the three and six months ended June 30, 2013, was $1.8 million and $3.6 million, respectively.