Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Deferred tax assets:
NOL and credit carryforwards	$ 142.0	$ 145.7
Pension, other postretirement and postemployment benefits	36.5	36.4
Payroll and compensation	17.1	19.0
Legal, environmental and self-insurance accruals	22.6	21.3
Working capital accruals	13.9	11.5
Other	7.9	7.1
Total deferred tax assets	240.0	241.0
Valuation allowance	(92.0)	(93.6)
Net deferred tax assets	148.0	147.4
Deferred tax liabilities:
Intangible assets recorded in acquisitions	74.9	75.1
Basis difference in affiliates	16.3	14.0
Accelerated depreciation	25.7	22.4
Deferred income	29.4	23.0
Other	4.2	1.6
Total deferred tax liabilities	150.5	136.1
Total deferred tax liabilities	$ (2.5)
Total deferred tax assets		$ 11.3

The tax effects as of the balance sheet date of the amount of excesses of tax deductions over taxable income in a year which cannot be used on the tax returns in the current year but may be carried forward to reduce taxable income or income taxes payable in a future year in certain jurisdictions and the tax effects arising from all unused tax credits available to reduce taxable income or income taxes payable in a future year, for which there must be sufficient tax-basis income to utilize a portion or all of the carryforward amount to realize the deferred tax asset.

No definition available.