Summary Of Accounting Policies And Accounting Changes - Schedule of New Accounting Pronouncement and Changes in Accounting Principle (Tables)

12 Months Ended

Dec. 31, 2012

Accounting Policies [Abstract]

Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block]

The following line items presented in the Consolidated Balance Sheets at December 31, 2012 and 2011 were affected by the adoption of the new accounting standard:

DOLLARS IN MILLIONS	As Computed without Change in Accounting		As Reported with Change in Accounting		Effect of Change
Impact on Assets at December 31, 2012:
Deferred Policy Acquisition Costs	$	467.7	$	303.4	$	(164.3	)
Total Assets	8,173.4		8,009.1		(164.3		)
Impact on Liabilities and Shareholders’ Equity at December 31, 2012:
Liabilities for Income Taxes	$	80.0	$	21.5	$	(58.5	)
Total Liabilities	5,905.9		5,847.4		(58.5		)
Retained Earnings	1,224.0		1,118.2		(105.8		)
Total Shareholders’ Equity	2,267.5		2,161.7		(105.8		)
Total Liabilities and Shareholders’ Equity	8,173.4		8,009.1		(164.3		)

DOLLARS IN MILLIONS	As Originally Reported		As Adjusted		Effect of Change
Impact on Assets at December 31, 2011:
Deferred Policy Acquisition Costs	$	448.5	$	294.0	$	(154.5	)
Current and Deferred Income Taxes	3.1		6.4		3.3
Total Assets	8,085.9		7,934.7		(151.2		)
Impact on Liabilities and Shareholders’ Equity at December 31, 2011:
Liabilities for Income Taxes	$	57.9	$	6.2	$	(51.7	)
Total Liabilities	5,869.8		5,818.1		(51.7		)
Retained Earnings	1,208.2		1,108.7		(99.5		)
Total Shareholders’ Equity	2,216.1		2,116.6		(99.5		)
Total Liabilities and Shareholders’ Equity	8,085.9		7,934.7		(151.2		)

NOTE 2. SUMMARY OF ACCOUNTING POLICIES AND ACCOUNTING CHANGES (Continued)

The following line items in the Consolidated Statement of Income for the year ended December 31, 2012 were affected by the adoption of the new accounting standard:

	Year Ended December 31, 2012
DOLLARS IN MILLIONS, EXCEPT PER SHARE AMOUNTS	As Computed without Change in Accounting			As Reported with Change in Accounting			Effect of Change
Total Revenues	$	2,462.3		$	2,462.3		$	—
Expenses:
Policyholders’ Benefits and Incurred Losses and Loss Adjustment Expenses	1,582.1			1,582.1			—
Insurance Expenses	662.5			672.3			9.8
Interest and Other Expenses	85.5			85.5			—
Total Expenses	2,330.1			2,339.9			9.8
Income from Continuing Operations before Income Taxes	132.2			122.4			(9.8		)
Income Tax Expense	(34.1		)	(30.6		)	3.5
Income from Continuing Operations	98.1			91.8			(6.3		)
Income from Discontinued Operations	11.6			11.6			—
Net Income	$	109.7		$	103.4		$	(6.3	)
Income from Continuing Operations per Unrestricted Share:
Basic	$	1.65		$	1.55		$	(0.10	)
Diluted	$	1.65		$	1.54		$	(0.11	)
Net Income Per Unrestricted Share:
Basic	$	1.85		$	1.75		$	(0.10	)
Diluted	$	1.85		$	1.74		$	(0.11	)

NOTE 2. SUMMARY OF ACCOUNTING POLICIES AND ACCOUNTING CHANGES (Continued)

The following line items in the Consolidated Statement of Income for the year ended December 31, 2011 were affected by the adoption of the new accounting standard:

	Year Ended December 31, 2011
DOLLARS IN MILLIONS, EXCEPT PER SHARE AMOUNTS	As Originally Reported			As Adjusted			Effect of Change
Total Revenues	$	2,495.0		$	2,495.0		$	—
Expenses:
Policyholders’ Benefits and Incurred Losses and Loss Adjustment Expenses	1,645.7			1,645.7			—
Insurance Expenses	669.3			683.6			14.3
Write-off of Goodwill and Other Intangibles Acquired	13.5			13.5			—
Interest and Other Expenses	83.9			83.9			—
Total Expenses	2,412.4			2,426.7			14.3
Income from Continuing Operations before Income Taxes	82.6			68.3			(14.3		)
Income Tax Expense	(11.7		)	(6.6		)	5.1
Income from Continuing Operations	70.9			61.7			(9.2		)
Income from Discontinued Operations	12.8			12.8			—
Net Income	$	83.7		$	74.5		$	(9.2	)
Income from Continuing Operations per Unrestricted Share:
Basic	$	1.17		$	1.02		$	(0.15	)
Diluted	$	1.17		$	1.02		$	(0.15	)
Net Income Per Unrestricted Share:
Basic	$	1.38		$	1.23		$	(0.15	)
Diluted	$	1.38		$	1.23		$	(0.15	)

NOTE 2. SUMMARY OF ACCOUNTING POLICIES AND ACCOUNTING CHANGES (Continued)

The following line items in the Consolidated Statement of Income for the year ended December 31, 2010 were affected by the adoption of the new accounting standard:

	Year Ended December 31, 2010
DOLLARS IN MILLIONS, EXCEPT PER SHARE AMOUNTS	As Originally Reported			As Adjusted			Effect of Change
Total Revenues	$	2,642.5		$	2,642.5		$	—
Expenses:
Policyholders’ Benefits and Incurred Losses and Loss Adjustment Expenses	1,647.2			1,647.2			—
Insurance Expenses	675.5			685.9			10.4
Write-off of Goodwill and Other Intangibles Acquired	14.8			14.8			—
Interest and Other Expenses	68.3			68.3			—
Total Expenses	2,405.8			2,416.2			10.4
Income from Continuing Operations before Income Taxes and Equity in Net Loss of Former Investee	236.7			226.3			(10.4		)
Income Tax Expense	(67.5		)	(63.8		)	3.7
Income from Continuing Operations before Equity in Net Loss of Former Investee	169.2			162.5			(6.7		)
Equity in Net Loss of Former Investee	(0.1		)	(0.1		)	—
Income from Continuing Operations	169.1			162.4			(6.7		)
Income from Discontinued Operations	15.5			15.5			—
Net Income	$	184.6		$	177.9		$	(6.7	)
Income from Continuing Operations per Unrestricted Share:
Basic	$	2.73		$	2.62		$	(0.11	)
Diluted	$	2.73		$	2.62		$	(0.11	)
Net Income Per Unrestricted Share:
Basic	$	2.98		$	2.87		$	(0.11	)
Diluted	$	2.98		$	2.87		$	(0.11	)

The following line items presented in the Consolidated Statements of Comprehensive Income for the years ended December 31, 2012, 2011 and 2010 were affected by the adoption of the new accounting standard:

	Year Ended December 31, 2012
DOLLARS IN MILLIONS	As Computed without Change in Accounting		As Reported with Change in Accounting		Effect of Change
Net Income	$	109.7	$	103.4	$	(6.3	)
Total Comprehensive Income	164.4		158.1		(6.3		)

	Year Ended December 31, 2011
DOLLARS IN MILLIONS	As Originally Reported		As Adjusted		Effect of Change
Net Income	$	83.7	$	74.5	$	(9.2	)
Total Comprehensive Income	184.3		175.1		(9.2		)

NOTE 2. SUMMARY OF ACCOUNTING POLICIES AND ACCOUNTING CHANGES (Continued)

	Year Ended December 31, 2010
DOLLARS IN MILLIONS	As Originally Reported		As Adjusted		Effect of Change
Net Income	$	184.6	$	177.9	$	(6.7	)
Total Comprehensive Income	283.2		276.5		(6.7		)

The following line items in the Consolidated Statements of Cash Flows for the years ended December 31, 2012, 2011 and 2010 were affected by the adoption of the new accounting standard:

	Year Ended December 31, 2012
DOLLARS IN MILLIONS	As Computed without Change in Accounting			As Reported with Change in Accounting			Effect of Change
Impact on Operating Activities:
Net Income	$	109.7		$	103.4		$	(6.3	)
Increase in Deferred Policy Acquisition Costs	(19.2		)	(9.4		)	9.8
Change in Income Taxes	(11.4		)	(14.9		)	(3.5		)
Net Cash Provided by Operating Activities	65.7			65.7			—

	Year Ended December 31, 2011
DOLLARS IN MILLIONS	As Originally Reported			As Adjusted			Effect of Change
Impact on Operating Activities:
Net Income	$	83.7		$	74.5		$	(9.2	)
Increase in Deferred Policy Acquisition Costs	(22.1		)	(7.8		)	14.3
Change in Income Taxes	22.3			17.2			(5.1		)
Net Cash Used by Operating Activities	(25.0		)	(25.0		)	—

	Year Ended December 31, 2010
DOLLARS IN MILLIONS	As Originally Reported			As Adjusted			Effect of Change
Impact on Operating Activities:
Net Income	$	184.6		$	177.9		$	(6.7	)
Increase in Deferred Policy Acquisition Costs	(15.1		)	(4.7		)	10.4
Change in Income Taxes	12.4			8.7			(3.7		)
Net Cash Provided by Operating Activities	58.5			58.5			—

Line items presented in the Investing Activities and Financing Activities sections of the Consolidated Statements of Cash Flows for the years ended December 31, 2012, 2011 and 2010 were unaffected by the adoption of the new accounting standard.