Fair Value of Assets and Liabilities - Fair Value Measurements (Details) - USD ($) $ in Millions | 6 Months Ended | |
Jun. 30, 2021 | Jun. 30, 2020 | Dec. 31, 2020 |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | | |
Fair Value Transfers Between Levels Amount | $ 0 | $ 0 | |
Fair Value, Measurements, Recurring [Member] | | | |
Fair value assets measured on recurring basis | | | |
Total | 15 | | $ 45.5 |
Fair value liabilities measured on recurring basis | | | |
Total | 7.8 | | 12.3 |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | | | |
Fair value assets measured on recurring basis | | | |
Total | 15 | | 43.8 |
Fair value liabilities measured on recurring basis | | | |
Total | 6.9 | | 6.6 |
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | | | |
Fair value assets measured on recurring basis | | | |
Total | 0 | | 1.7 |
Fair value liabilities measured on recurring basis | | | |
Total | 0.9 | | 5.7 |
Assets held in rabbi trusts [Member] | | | |
Fair value assets measured on recurring basis | | | |
Fair value of investment assets | 6.9 | | 6.6 |
Short-term investments | Certificates of deposit | Fair Value, Measurements, Recurring [Member] | | | |
Fair value assets measured on recurring basis | | | |
Fair value of investment assets | 8.1 | | 37.2 |
Short-term investments | Certificates of deposit | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | | | |
Fair value assets measured on recurring basis | | | |
Fair value of investment assets | 8.1 | | 37.2 |
Short-term investments | Certificates of deposit | Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | | | |
Fair value assets measured on recurring basis | | | |
Fair value of investment assets | 0 | | 0 |
Securities and other investments | Assets held in rabbi trusts [Member] | Fair Value, Measurements, Recurring [Member] | | | |
Fair value assets measured on recurring basis | | | |
Assets held in rabbi trusts | 6.9 | | 6.6 |
Securities and other investments | Assets held in rabbi trusts [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | | | |
Fair value assets measured on recurring basis | | | |
Assets held in rabbi trusts | 6.9 | | 6.6 |
Securities and other investments | Assets held in rabbi trusts [Member] | Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | | | |
Fair value assets measured on recurring basis | | | |
Assets held in rabbi trusts | 0 | | 0 |
Other current assets | Foreign exchange forward contracts | Fair Value, Measurements, Recurring [Member] | | | |
Fair value assets measured on recurring basis | | | |
Derivative Asset | 0 | | 1.7 |
Other current assets | Foreign exchange forward contracts | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | | | |
Fair value assets measured on recurring basis | | | |
Derivative Asset | 0 | | 0 |
Other current assets | Foreign exchange forward contracts | Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | | | |
Fair value assets measured on recurring basis | | | |
Derivative Asset | 0 | | 1.7 |
Other current liabilities | Foreign exchange forward contracts | Fair Value, Measurements, Recurring [Member] | | | |
Fair value liabilities measured on recurring basis | | | |
Derivative Liability | 0.2 | | 2.7 |
Other current liabilities | Foreign exchange forward contracts | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | | | |
Fair value liabilities measured on recurring basis | | | |
Derivative Liability | 0 | | 0 |
Other current liabilities | Foreign exchange forward contracts | Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | | | |
Fair value liabilities measured on recurring basis | | | |
Derivative Liability | 0.2 | | 2.7 |
Other liabilities | Fair Value, Measurements, Recurring [Member] | | | |
Fair value liabilities measured on recurring basis | | | |
Deferred compensation | 6.9 | | 6.6 |
Other liabilities | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | | | |
Fair value liabilities measured on recurring basis | | | |
Deferred compensation | 6.9 | | 6.6 |
Other liabilities | Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | | | |
Fair value liabilities measured on recurring basis | | | |
Deferred compensation | 0 | | 0 |
Other liabilities | Interest rate swaps | Fair Value, Measurements, Recurring [Member] | | | |
Fair value liabilities measured on recurring basis | | | |
Derivative Liability | 0.7 | | 3 |
Other liabilities | Interest rate swaps | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | | | |
Fair value liabilities measured on recurring basis | | | |
Derivative Liability | 0 | | 0 |
Other liabilities | Interest rate swaps | Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | | | |
Fair value liabilities measured on recurring basis | | | |
Derivative Liability | $ 0.7 | | $ 3 |