Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies - Change in Accounting Principle Impact of Balance Sheet (Details)

v3.7.0.1
Summary of Significant Accounting Policies - Change in Accounting Principle Impact of Balance Sheet (Details) - USD ($)
$ in Millions
Dec. 31, 2016
Dec. 31, 2015
Jan. 01, 2014
Assets      
Inventories, net $ 272.1 $ 253.0  
Income tax receivable 2.4 0.0  
Deferred income taxes, noncurrent 4.5    
Liabilities      
Deferred income taxes, noncurrent 8.4    
Deferred income taxes, current   1.4  
Stockholders' equity:      
Additional paid-in capital 673.3 0.0  
Retained earnings 10.0 0.0  
Net AWI investment 0.0 622.0 $ 553.1
Inventory Valuation Adjustment - LIFO to FIFO | As Computed under LIFO      
Stockholders' equity:      
Net AWI investment     $ 534.3
Wood Flooring      
Assets      
Inventories, net   253.0  
Deferred income taxes, current   0.0  
Liabilities      
Deferred income taxes, current   1.4  
Stockholders' equity:      
Net AWI investment   622.0  
Wood Flooring | Inventory Valuation Adjustment - LIFO to FIFO      
Assets      
Inventories, net 272.1    
Income tax receivable 2.4    
Deferred income taxes, noncurrent 4.5    
Liabilities      
Deferred income taxes, noncurrent 8.4    
Stockholders' equity:      
Additional paid-in capital 673.3    
Retained earnings 10.0    
Wood Flooring | Inventory Valuation Adjustment - LIFO to FIFO | As Computed under LIFO      
Assets      
Inventories, net 251.6 242.8  
Income tax receivable 4.7    
Deferred income taxes, current   3.0  
Deferred income taxes, noncurrent 5.3    
Liabilities      
Deferred income taxes, noncurrent 3.8    
Deferred income taxes, current   0.3  
Stockholders' equity:      
Additional paid-in capital 666.4    
Retained earnings 4.1    
Net AWI investment   615.9  
Wood Flooring | Inventory Valuation Adjustment - LIFO to FIFO | Effect of Change      
Assets      
Inventories, net 20.5 10.2  
Income tax receivable (2.3)    
Deferred income taxes, current   (3.0)  
Deferred income taxes, noncurrent (0.8)    
Liabilities      
Deferred income taxes, noncurrent 4.6    
Deferred income taxes, current   1.1  
Stockholders' equity:      
Additional paid-in capital 6.9    
Retained earnings $ 5.9    
Net AWI investment   $ 6.1