Adjustments to Additional Paid-in Capital, Capped Call on Debt Exchange

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Consolidated Statements of Deficit - USD ($) $ in Millions	12 Months Ended
Consolidated Statements of Deficit - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2018	Jan. 01, 2017
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	$ (1,299.6)	$ (1,326.5)	$ (1,647.4)
Reclassification pursuant to ASU No. 2018-02		0.0
Consolidated net income (loss)	(13.3)	78.9	(66.6)
Stock-based activity	8.0	11.1	9.0
Debt exchange	83.9
Capped call on debt exchange	7.2
Translation adjustments	24.4	(81.8)	117.8
Postretirement plans	(38.9)	33.8	265.1
Ending Balance	(1,228.3)	(1,299.6)	(1,326.5)
ASU No. 2016-16
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect adjustment					$ (4.4)
ASU No. 2014-09
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect adjustment				$ (21.4)
ASU No. 2017-05
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect adjustment				6.3
Total Unisys Corporation
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	(1,343.5)	(1,354.7)	(1,631.0)
Reclassification pursuant to ASU No. 2018-02		0.0
Consolidated net income (loss)	(17.2)	75.5	(65.3)
Stock-based activity	8.0	11.1	9.0
Debt exchange	83.9
Capped call on debt exchange	7.2
Translation adjustments	23.8	(79.7)	110.1
Postretirement plans	(27.6)	19.4	226.9
Ending Balance	(1,265.4)	(1,343.5)	(1,354.7)
Total Unisys Corporation \| ASU No. 2016-16
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect adjustment					(4.4)
Total Unisys Corporation \| ASU No. 2014-09
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect adjustment				(21.4)
Total Unisys Corporation \| ASU No. 2017-05
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect adjustment				6.3
Common Stock Par Value
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	0.5	0.5	0.5
Stock-based activity	0.1
Debt exchange	0.1
Ending Balance	0.7	0.5	0.5
Accumulated Deficit
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	(1,694.0)	(1,963.1)	(1,893.4)
Reclassification pursuant to ASU No. 2018-02		208.7
Consolidated net income (loss)	(17.2)	75.5	(65.3)
Ending Balance	(1,711.2)	(1,694.0)	(1,963.1)
Accumulated Deficit \| ASU No. 2016-16
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect adjustment					$ (4.4)
Accumulated Deficit \| ASU No. 2014-09
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect adjustment				(21.4)
Accumulated Deficit \| ASU No. 2017-05
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect adjustment				$ 6.3
Treasury Stock At Cost
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	(105.0)	(102.7)	(100.5)
Stock-based activity	(4.6)	(2.3)	(2.2)
Ending Balance	(109.6)	(105.0)	(102.7)
Paid-in Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	4,539.8	4,526.4	4,515.2
Stock-based activity	12.5	13.4	11.2
Debt exchange	83.8
Capped call on debt exchange	7.2
Ending Balance	4,643.3	4,539.8	4,526.4
Accumulated Other Comprehensive Loss
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	(4,084.8)	(3,815.8)	(4,152.8)
Reclassification pursuant to ASU No. 2018-02		(208.7)
Translation adjustments	23.8	(79.7)	110.1
Postretirement plans	(27.6)	19.4	226.9
Ending Balance	(4,088.6)	(4,084.8)	(3,815.8)
Noncontrolling Interests
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	43.9	28.2	(16.4)
Consolidated net income (loss)	3.9	3.4	(1.3)
Translation adjustments	0.6	(2.1)	7.7
Postretirement plans	(11.3)	14.4	38.2
Ending Balance	$ 37.1	$ 43.9	$ 28.2