Schedule I - Condensed Financial Information of the Parent (Condensed Balance Sheets) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
ASSETS
Cash and cash equivalents	$ 139.9	$ 153.7	$ 92.4	$ 93.0
Property, Plant and Equipment, Net	183.0	107.2
Other Non-current Assets	36.7	48.9
Total Assets	776.3	1,808.7	1,670.9
LIABILITIES AND EQUITY
Current liabilities	227.2	891.2
Other Long-term Liabilities	51.6	39.8
Stockholders’ equity	281.4	576.2
Liabilities and Equity	776.3	1,808.7
Parent Company
ASSETS
Cash and cash equivalents	120.7	130.7	29.6	48.8
Other current assets	4.2	6.3
Investment in subsidiaries	203.4	490.7
Property, Plant and Equipment, Net	1.6	1.9
Other Non-current Assets	4.2	6.8
Total Assets	334.1	636.4
LIABILITIES AND EQUITY
Current liabilities	6.6	15.7
Current intercompany accounts payable, net	12.9	9.3
Other Long-term Liabilities	12.8	12.8
Stockholders’ equity	281.4	576.2
Liabilities and Equity	334.1	636.4
HBB | Parent Company
ASSETS
Investment in subsidiaries	43.1	35.0
KC | Parent Company
ASSETS
Investment in subsidiaries	43.7	46.7
NACoal | Parent Company
ASSETS
Investment in subsidiaries	102.3	96.1
Other | Parent Company
ASSETS
Investment in subsidiaries	14.3	16.6
Bellaire
LIABILITIES AND EQUITY
Note payable to Bellaire	$ 20.4	$ 22.4