7. RESTRUCTURING, IMPAIRMENT AND PLANT CLOSING COSTS

As of  September 30, 2021 and December 31, 2020, accrued restructuring costs by type of cost and initiative consisted of the following (dollars in millions):

Details with respect to our reserves for restructuring, impairment and plant closing costs by segment and initiative are provided below (dollars in millions):

Details with respect to cash and noncash restructuring charges from continuing operations for the three and nine months ended September 30, 2021 and 2020 are provided below (dollars in millions):

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2021 Restructuring Activities 

Beginning in the first quarter of 2021, our Corporate and other segment incurred restructuring costs related to a restructuring program to optimize our global approach to leveraging shared services capabilities. In connection with this restructuring program, we recorded restructuring expense of approximately $16 million in the nine months ended September 30, 2021 primarily related to workforce reductions, and we expect to record further restructuring expenses of approximately $3 million through 2023. 

Beginning in the third quarter of 2020, our Polyurethanes segment implemented a restructuring program to optimize its downstream footprint. In connection with this restructuring program, we recorded restructuring expense of approximately $4 million in the nine months ended September 30, 2021 primarily related to workforce reductions and accelerated depreciation, partially offset by a gain on sale of assets of approximately $3 million. We expect to record further restructuring expenses of between approximately $4 million and $5 million through the first half of 2022.

Beginning in the second quarter of 2020, our Advanced Materials segment implemented restructuring programs in connection with the CVC Thermoset Specialties Acquisition, the alignment of the segment’s commercial organization and optimization of the segment’s manufacturing processes. In connection with these restructuring programs, we recorded restructuring expense of approximately $8 million in the nine months ended September 30, 2021 primarily related to accelerated depreciation.

2020 Restructuring Activities

Beginning in the second quarter of 2020, our Polyurethanes segment implemented a restructuring program to reorganize its spray polyurethane foam business to better position this business for efficiencies and growth in coming years. In connection with this restructuring program, we recorded restructuring expense of approximately $6 million in the nine months ended September 30, 2020 primarily related to workforce reductions and accelerated depreciation.

Beginning in the third quarter of 2020, our Polyurethanes segment implemented a restructuring program to optimize its downstream footprint. In connection with this restructuring program, we recorded restructuring expense of approximately $1 million in the third quarter of 2020.

Beginning in the second quarter of 2020, our Performance Products segment implemented a restructuring program, primarily related to workforce reductions, in response to the sale of our Chemical Intermediates Businesses to Indorama. In connection with this restructuring program, we recorded restructuring expense of approximately $4 million in the nine months ended September 30, 2020.

Beginning in the second quarter of 2020, our Advanced Materials segment implemented restructuring programs, primarily related to workforce reductions, in connection with the CVC Thermoset Specialties Acquisition and the alignment of the segment's commercial organization and optimization of the segment's manufacturing processes. In connection with these restructuring programs, we recorded restructuring expense of approximately $10 million in the nine months ended September 30, 2020.

During 2020, our Textile Effects segment implemented restructuring programs to rationalize and realign structurally across various functions and certain locations within the segment. In connection with these restructuring programs, we recorded restructuring expense of approximately $10 million in the nine months ended September 30, 2020, related primarily to workforce reductions.