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

9 Months Ended

Sep. 30, 2018

Losses and Loss Expenses Payable [Abstract]

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

($ millions)	2018			2017
Losses and loss expenses payable, at beginning of period	$	1,255.6		$	1,181.6
Less: reinsurance recoverable on losses and loss expenses payable	3.1			3.6
Net balance at beginning of period	1,252.5			1,178.0
Incurred related to:
Current year	678.7			752.8
Prior years	(57.6		)	(34.6		)
Total incurred	621.1			718.2
Paid related to:
Current year	314.1			302.0
Prior years	365.8			318.3
Total paid	679.9			620.3
Net balance at end of period	1,193.7			1,275.9
Plus: reinsurance recoverable on losses and loss expenses payable	5.0			4.9
Losses and loss expenses payable, at end of period	$	1,198.7		$	1,280.8