Guarantees (Tables)

9 Months Ended

Sep. 30, 2017

Service and Product Warranties and Product Performance Guarantees [Abstract]

Product Warranty Disclosure [Table Text Block]

The changes in the carrying amount of service and product warranties and product performance guarantees for the nine months ended September 30, 2017 and 2016 are as follows:

(Dollars in millions)	2017			2016
Balance as of January 1	$	1,199		$	1,212
Warranties and performance guarantees issued	221			218
Settlements made	(194		)	(192		)
Other	21			—
Balance as of September 30	$	1,247		$	1,238