Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2017

Accounting Policies [Abstract]

Summary of Deferred Policy Acquisition Cost Amortization and Net Advertising Expense [Table Text Block]

The table below presents a summary of deferred policy acquisition cost amortization and net advertising expense:

	Year Ended December 31,
	2017		2016		2015
	(Amounts in millions)
Deferred policy acquisition cost amortization	$	555.4	$	562.5	$	539.2
Net advertising expense	37.4		39.6		44.0