Revenue Recognition (Details) - USD ($) $ in Millions		12 Months Ended
	Jan. 01, 2018	Dec. 31, 2018	Dec. 31, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Effect of LIFO Inventory Liquidation on Income	$ 5.0
Contract assets	55.6	$ 54.9	$ 0.0
Inventories	167.2	215.1	207.9
Total current assets	671.5	656.6	656.6
Deferred tax assets, net	68.7	35.9	72.0
Total assets	1,396.8	1,419.3	1,385.2
Other accrued liabilities	42.0	44.0	40.5
Total current liabilities	174.6	205.5	173.1
Total liabilities	640.4	678.9	638.9
Retained earnings	95.6	150.2	85.5
Total stockholders' equity	756.4	740.4	746.3
Total liabilities and stockholders' equity	1,396.8	1,419.3	1,385.2
Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Contract assets		0.0	0.0
Inventories		247.5	207.9
Total current assets		634.1	656.6
Deferred tax assets, net		39.2	72.0
Total assets		1,400.1	1,385.2
Other accrued liabilities		40.3	40.5
Total current liabilities		201.8	173.1
Total liabilities		675.2	638.9
Retained earnings		134.7	85.5
Total stockholders' equity		724.9	746.3
Total liabilities and stockholders' equity		1,400.1	$ 1,385.2
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Contract assets	55.6	(54.9)
Inventories	(40.7)	32.4
Total current assets	14.9	(22.5)
Deferred tax assets, net	(3.3)	3.3
Total assets	11.6	(19.2)
Other accrued liabilities	1.5	(3.7)
Total current liabilities	1.5	(3.7)
Total liabilities	1.5	(3.7)
Retained earnings	10.1	(15.5)
Total stockholders' equity	10.1	(15.5)
Total liabilities and stockholders' equity	$ 11.6	(19.2)
Imperial Machine and Tool Co. (''IMT'') [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Acquisition-related costs		$ 0.6