Stock Compensation Plans (Tables)

6 Months Ended

Jun. 30, 2015

Stock Compensation Plans [Abstract]

Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan [Table Text Block]

Stock-based compensation expense for the following periods was:

In millions	Three months ended June 30		Six months ended June 30
	2015	2014	2015	2014
Restricted stock expense	$11	$9	$20	$19
Tax benefit	(3)	(2)	(6)	(6)
Total stock-based compensation (net of tax)	$8	$7	$14	$13