Reserve for Property and Liability Insurance Claims and Claims Expense (Tables)

6 Months Ended

Jun. 30, 2018

Reserve for Property-Liability Insurance Claims and Claims Expense [Abstract]

Schedule of liability for unpaid claims and claims adjustment expense

Rollforward of the reserve for property and casualty insurance claims and claims expense
	Six months ended June 30,
($ in millions)	2018			2017
Balance as of January 1	$	26,325		$	25,250
Less reinsurance recoverables	(6,471		)	(6,184		)
Net balance as of January 1	19,854			19,066
SquareTrade acquisition as of January 3, 2017	—			17
Incurred claims and claims expense related to:
Current year	11,089			11,291
Prior years	(148		)	(186		)
Total incurred	10,941			11,105
Claims and claims expense paid related to:
Current year	(5,870		)	(6,060		)
Prior years	(4,809		)	(4,450		)
Total paid	(10,679		)	(10,510		)
Net balance as of June 30	20,116			19,678
Plus reinsurance recoverables	6,507			6,206
Balance as of June 30	$	26,623		$	25,884