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Revenue from Contracts with Customers - Contract Assets and Liabilities (Details) - USD ($) $ in Millions | 6 Months Ended
--- | ---
Jun. 30, 2021 | Jun. 30, 2020
Contract Assets, Current [Roll Forward] |  |
Balance as of beginning of fiscal year | $ 38.9 | $ 38.5
Recognized in current year | 48.9 | 37.5
Reclassified to accounts receivable | (30.4) | (34.5)
Impairment | 0.0 | 0.0
Reclassification to/from long-term and contract liability | (5.1) | 0.1
Balance as of period end | 52.3 | 41.6
Contract Assets, Noncurrent [Roll Forward] |  |
Balance as of beginning of fiscal year | 0.0 | 0.1
Recognized in current year | 0.0 | 0.0
Reclassified to accounts receivable | 0.0 | 0.0
Impairment | 0.0 | 0.0
Reclassification to/from short-term | 0.0 | (0.1)
Balance as of period end | 0.0 | 0.0
Contract Liabilities, Current [Roll Forward] |  |
Balance as of beginning of fiscal year | 111.8 | 78.7
Recognized in current year | 77.9 | 97.9
Amounts in beginning balance reclassified to revenue | (63.9) | (33.9)
Current year amounts reclassified to revenue | (18.7) | (38.5)
Other | 0.0 | (0.2)
Reclassification to/from long-term and contract asset | (3.3) | 5.8
Balance as of period end | 103.8 | 109.8
Contract Liabilities, Noncurrent [Roll Forward] |  |
Balance as of beginning of fiscal year | 32.0 | 25.9
Recognized in current year | 41.0 | 12.4
Amounts in beginning balance reclassified to revenue | (0.5) | (0.5)
Current year amounts reclassified to revenue | 0.0 | 0.0
Other | 0.0 | 0.0
Reclassification to/from short-term | (1.8) | (5.8)
Balance as of period end | $ 70.7 | $ 32.0

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- Definition Change in Contract with Customer, Liability, Current [Roll Forward] + References No definition available. + Details
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- Definition Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=123360276&loc=SL49130531-203044 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=123360276&loc=SL49130533-203044 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130549-203045 + Details
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