Losses and Loss Expenses Payable Losses and Loss Expenses Payable (Tables)

6 Months Ended

Jun. 30, 2017

Losses and Loss Expenses Payable [Abstract]

Schedule Of Activity In Liability For Unpaid Losses And Loss Adjustment Expenses Table [Table Text Block]

($ millions)	2017			2016
Losses and loss expenses payable, at beginning of period	$	1,181.6		$	1,053.0
Less: reinsurance recoverable on losses and loss expenses payable	3.6			5.9
Net balance at beginning of period	1,178.0			1,047.1
Incurred related to:
Current year	489.8			457.7
Prior years	(25.4		)	30.2
Total incurred	464.4			487.9
Paid related to:
Current year	174.3			159.3
Prior years	237.2			238.6
Total paid	411.5			397.9
Net balance at end of period	1,230.9			1,137.1
Plus: reinsurance recoverable on losses and loss expenses payable	2.7			6.1
Losses and loss expenses payable, at end of period	$	1,233.6		$	1,143.2