Accounting for Transfers and Servicing of Financial Assets and Variable Interest Entities (Tables)

12 Months Ended

Dec. 31, 2017

Accounting Policies [Abstract]

Summary of Investments in Community Development and Tax-advantaged VIEs

The following table provides a summary of investments in community development and tax-advantaged VIEs that the Company has not consolidated:

At December 31 (Dollars in Millions)	2017		2016
Investment carrying amount	$	5,660	$	5,009
Unfunded capital and other commitments		2,770		2,477
Maximum exposure to loss		12,120		10,373