Consolidated Statements of Changes in Shareholders' Equity Statement - USD ($) $ in Millions	Total	AOCI Attributable to Parent [Member]	Common Stock [Member]	Treasury Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]
Common Stock, Shares, Issued			67,500,000
Shares, Issued				(32,700,000)
Stockholders' Equity Attributable to Parent		$ (163.6)		$ (1,364.5)	$ 720.1	$ 2,601.3
Common Stock, Value, Issued			$ 41.8
Dividends Declared [Table Text Block]	0.96
Stock Repurchased During Period, Shares	0
Repurchase of common stock	$ 0.0
APIC, Share-based Payment Arrangement, Increase for Cost Recognition					8.7
Stock Issued During Period, Shares, New Issues			200,000
Stock Issued During Period, Value, New Issues			$ 0.0
Net income	85.6
Dividends, Common Stock, Cash						(35.2)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	$ 18.9
Common Stock, Shares, Issued			67,600,000
Shares, Issued				(32,700,000)
Stockholders' Equity Attributable to Parent		(201.7)		$ (1,364.5)	725.4	2,630.0
Common Stock, Value, Issued			$ 41.8
Dividends Declared [Table Text Block]	0.48
Stock Repurchased During Period, Shares	0
Repurchase of common stock	$ 0.0
APIC, Share-based Payment Arrangement, Increase for Cost Recognition					3.4
Stock Issued During Period, Shares, New Issues			100,000
Stock Issued During Period, Value, New Issues			$ 0.0
Net income	39.3
Dividends, Common Stock, Cash						(17.6)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(19.2)
Common Stock, Shares, Issued			67,700,000
Shares, Issued				(32,700,000)
Stockholders' Equity Attributable to Parent	$ 1,875.3	(182.5)		$ (1,364.5)	728.8	2,651.7
Common Stock, Value, Issued			$ 41.8
Common Stock, Shares, Issued	67,751,074		67,800,000
Shares, Issued				(32,700,000)
Stockholders' Equity Attributable to Parent	$ 1,957.4	(137.5)		$ (1,364.5)	735.4	2,682.1
Common Stock, Value, Issued	$ 41.9		$ 41.9
Dividends Declared [Table Text Block]	1.00
Stock Repurchased During Period, Shares	0
Repurchase of common stock	$ 0.0
APIC, Share-based Payment Arrangement, Increase for Cost Recognition					24.0
Stock Issued During Period, Shares, New Issues			400,000
Stock Issued During Period, Value, New Issues			$ 0.3
Net income	42.0
Dividends, Common Stock, Cash						(36.8)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	$ 15.5
Common Stock, Shares, Issued			68,100,000
Shares, Issued				(32,700,000)
Stockholders' Equity Attributable to Parent		(171.0)		$ (1,364.5)	753.1	2,700.3
Common Stock, Value, Issued			$ 42.1
Dividends Declared [Table Text Block]	0.50
Stock Repurchased During Period, Shares	0
Repurchase of common stock	$ 0.0
APIC, Share-based Payment Arrangement, Increase for Cost Recognition					6.3
Stock Issued During Period, Shares, New Issues			100,000
Stock Issued During Period, Value, New Issues			$ 0.1
Net income	5.5
Dividends, Common Stock, Cash						(18.5)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	$ (18.0)
Common Stock, Shares, Issued	68,175,553		68,200,000
Shares, Issued				(32,700,000)
Stockholders' Equity Attributable to Parent	$ 1,971.4	$ (153.0)		$ (1,364.5)	$ 759.4	$ 2,687.3
Common Stock, Value, Issued	$ 42.2		$ 42.2