v3.20.2

Employee Benefit Plans Schedule of Amounts Recognized in Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Changes in AOCL [Roll Forward]
Beginning balance	$ 2,543,977	$ 2,616,255	$ 2,715,028	$ 2,643,434
Net actuarial gain (loss)	414	(10,913)	(333)	(10,913)
Curtailment gain	0	0	1,703	0
Recognition of prior service credit amortization in income	(45)	(45)	(90)	(90)
Recognition of actuarial loss amortization in income	1,458	1,625	2,989	2,973
Recognition of settlement cost in income	0	2,060	969	2,060
Ending balance	2,454,738	2,637,779	2,454,738	2,637,779
Pension Plan [Member]
Changes in AOCL [Roll Forward]
Net actuarial gain (loss)	1,560	(10,029)	813	(10,029)
Curtailment gain			1,703	0
Recognition of prior service credit amortization in income	(45)	(45)	(90)	(90)
Recognition of actuarial loss amortization in income	1,322	1,508	2,734	2,785
Recognition of settlement cost in income	0	2,060	969	2,060
Other Postretirement Benefits Plan [Member]
Changes in AOCL [Roll Forward]
Net actuarial gain (loss)	(1,146)	(884)	(1,146)	(884)
Curtailment gain			0	0
Recognition of prior service credit amortization in income	0	0	0	0
Recognition of actuarial loss amortization in income	136	117	255	188
Recognition of settlement cost in income	0	0	0	0
Accumulated Other Comprehensive Loss | Pension Plan [Member]
Changes in AOCL [Roll Forward]
Beginning balance	(101,447)	(87,370)	(104,739)	(88,602)
Ending balance	(98,610)	(93,876)	(98,610)	(93,876)
Accumulated Other Comprehensive Loss | Other Postretirement Benefits Plan [Member]
Changes in AOCL [Roll Forward]
Beginning balance	(8,259)	(5,338)	(8,378)	(5,409)
Ending balance	$ (9,269)	$ (6,105)	$ (9,269)	$ (6,105)

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Amount of gain (loss) recognized in net periodic benefit (cost) credit from settlement and curtailment.

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