Business Developments - Changes in Reserves Associated with Strategic Initiatives (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2021
Restructuring Reserve [Roll Forward]
Beginning balance	$ 22,915	$ 19,795
Charged to earnings	1,138	10,579
Charged against assets	(362)	(2,175)
Cash payments	(7,497)	(12,005)
Ending balance	16,194	16,194
Employee Severance
Restructuring Reserve [Roll Forward]
Beginning balance	18,370	17,675
Charged to earnings	45	2,105
Charged against assets	0	0
Cash payments	(4,451)	(5,816)
Ending balance	13,964	13,964
Other Restructuring
Restructuring Reserve [Roll Forward]
Beginning balance	4,545	2,120
Charged to earnings	1,063	8,265
Charged against assets	(332)	(1,966)
Cash payments	(3,046)	(6,189)
Ending balance	2,230	2,230
Right-of-Use Asset Charges
Restructuring Reserve [Roll Forward]
Beginning balance	0	0
Charged to earnings	30	209
Charged against assets	(30)	(209)
Cash payments	0	0
Ending balance	$ 0	$ 0

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of decrease in the reserve for full or partial settlement through consideration other than cash.

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