Mortgage Servicing Assets (Tables)

12 Months Ended

Dec. 31, 2016

Commercial Mortgage Backed Securities [Member]

Servicing Assets at Fair Value [Line Items]

Changes in Carrying Amount of Mortgage Servicing Assets

Changes in the carrying amount of commercial mortgage servicing assets are summarized as follows:



Year ended December 31, in millions	2016			2015
Balance at beginning of period	$	322		$	323
Servicing retained from loan sales	80			55
Purchases	41			38
Amortization	(87		)	(94		)
Balance at end of period	$	356		$	322
Fair value at end of period	$	459		$	423

Schedule of Range and Weighted-Average of Significant Unobservable Inputs

The range and weighted-average of the significant unobservable inputs used to fair value our commercial mortgage servicing assets at December 31, 2016, and December 31, 2015, along with the valuation techniques, are shown in the following table:



December 31, 2016	Valuation Technique	Significant Unobservable Input	Range (Weighted-Average)
dollars in millions	Valuation Technique	Significant Unobservable Input	Range (Weighted-Average)
Commercial mortgage servicing assets	Discounted cash flow	Expected defaults	1.00 - 3.00% (1.40%)
		Residual cash flows discount rate	7.00 - 12.00% (8.00%)
		Escrow earn rate	1.10 - 3.00% (2.40%)
		Servicing cost	$150 - $2,700 ($1,124)
		Loan assumption rate	0.00 - 3.00% (1.13%)
		Percentage late	0.00 - 2.00% (0.34%)



December 31, 2015	Valuation Technique	Significant Unobservable Input	Range (Weighted-Average)
dollars in millions	Valuation Technique	Significant Unobservable Input	Range (Weighted-Average)
Commercial mortgage servicing assets	Discounted cash flow	Expected defaults	1.00 - 3.00% (1.70%)
		Residual cash flows discount rate	7.00 - 15.00% (7.80%)
		Escrow earn rate	1.00 - 3.50% (2.30%)
		Servicing cost	$150 - $2,700 ($1,215)
		Loan assumption rate	0.00 - 3.00% (1.34%)
		Percentage late	0.00 - 2.00% (0.33%)

Residential Mortgage Backed Securities [Member]

Servicing Assets at Fair Value [Line Items]

Changes in Carrying Amount of Mortgage Servicing Assets

Changes in the carrying amount of residential mortgage servicing assets are summarized as follows:



in millions	2016
Balance at beginning of period	—
Servicing retained from loan sales	$	2
Purchases	28
Amortization	(2		)
Balance at end of period	$	28
Fair value at end of period	$	33

Schedule of Range and Weighted-Average of Significant Unobservable Inputs

The range and weighted-average of the significant unobservable inputs used to fair value our residential mortgage servicing assets at December 31, 2016, along with the valuation techniques, are shown in the following table:



December 31, 2016	Valuation Technique	Significant Unobservable Input	Range (Weighted-Average)
dollars in millions	Valuation Technique	Significant Unobservable Input	Range (Weighted-Average)
Residential mortgage servicing assets	Discounted cash flow	Prepayment speed	7.79 - 18.61% (9.42%)
		Discount rate	8.50 - 11.00% (8.55%)
		Servicing cost	$76 - $3,335 ($83.04)