Employee Benefits (Tables)

6 Months Ended

Jun. 30, 2021

Retirement Benefits [Abstract]

Schedule of Components of Net Periodic Pension Benefit (Income) Expense and Post-retirement Benefit Expense

Net periodic benefit income for the Lumen Combined Pension Plan ("Combined Pension Plan") includes the following components:

	Combined Pension Plan
	Three Months Ended June 30,			Six Months Ended June 30,
	2021		2020	2021	2020
	(Dollars in millions)
Service cost	$	15	13	28	29
Interest cost	49		80	99	162
Expected return on plan assets	(138)		(149)	(276)	(298)
Recognition of prior service credit	(3)		(1)	(5)	(4)
Recognition of actuarial loss	49		52	98	102
Net periodic pension benefit income	$	(28)	(5)	(56)	(9)

Net periodic benefit expense for our post-retirement benefit plans includes the following components:

	Post-Retirement Benefit Plans
	Three Months Ended June 30,			Six Months Ended June 30,
	2021		2020	2021	2020
	(Dollars in millions)
Service cost	$	3	3	7	7
Interest cost	11		20	23	40
Recognition of prior service cost	4		4	8	8
Recognition of actuarial loss	1		—	2	—
Net periodic post-retirement benefit expense	$	19	27	40	55