Employee Benefits (Tables)

12 Months Ended

Dec. 31, 2015

Dec. 31, 2014

Employee Benefits

Schedule of estimated future benefit payments

The estimated benefit payments provided below are based on actuarial assumptions using the demographics of the employee and retiree populations and have been reduced by estimated participant contributions.

	Pension Plans		Post-Retirement Benefit Plans	Medicare Part D Subsidy Receipts
	(Dollars in millions)
Estimated future benefit payments:
2016	$	1,059	309	(7	)
2017	1,010		300	(7	)
2018	991		290	(7	)
2019	973		283	(7	)
2020	954		276	(7	)
2021 - 2025	4,433		1,256	(30	)

Schedule of actuarial assumptions used to compute net periodic benefit expense

The actuarial assumptions used to compute the net periodic benefit expense for our qualified pension, non-qualified pension and post-retirement benefit plans are based upon information available as of the beginning of the year, as presented in the following table.

	Pension Plans						Post-Retirement Benefit Plans
	2015		2014		2013		2015		2014		2013
Actuarial assumptions at beginning of year:
Discount rate	3.50% - 4.10%		4.20% - 5.10%		3.50% - 4.20%		3.80	%	4.50	%	3.60	%
Rate of compensation increase	3.25	%	3.25	%	3.25	%	N/A		N/A		N/A
Expected long-term rate of return on plan assets	7.50	%	7.50	%	7.50	%	7.50	%	6.00% - 7.50%		6.00% - 7.30%
Initial health care cost trend rate	N/A		N/A		N/A		6.00% / 6.50%		6.00% / 6.50%		6.50% / 7.00%
Ultimate health care cost trend rate	N/A		N/A		N/A		4.50	%	4.50	%	4.50	%
Year ultimate trend rate is reached	N/A		N/A		N/A		2025		2024		2022

_______________________________________________________________________________

N/A-Not applicable

Schedule of actuarial assumptions used to compute the funded status for the plans

The actuarial assumptions used to compute the funded status for the plans are based upon information available as of December 31, 2015 and 2014 and are as follows:

	Pension Plans				Post-Retirement Benefit Plans
	December 31,				December 31,
	2015		2014		2015		2014
Actuarial assumptions at end of year:
Discount rate	3.50% - 4.50%		3.50% - 4.10%		4.15	%	3.80	%
Rate of compensation increase	3.25	%	3.25	%	N/A		N/A
Initial health care cost trend rate	N/A		N/A		5.00% / 5.25%		6.00% / 6.50%
Ultimate health care cost trend rate	N/A		N/A		4.50	%	4.50	%
Year ultimate trend rate is reached	N/A		N/A		2025		2024

_______________________________________________________________________________

N/A-Not applicable

Schedule of change in plan assets

The following tables summarize the change in the fair value of plan assets for the pension and post-retirement benefit plans:

	Pension Plans Years Ended December 31,
	2015			2014		2013
	(Dollars in millions)
Change in plan assets
Fair value of plan assets at beginning of year	$	12,571		12,346		12,321
Return on plan assets	(161		)	1,373		810
Employer contributions	100			157		146
Settlements	—			(460	)	—
Benefits paid from plan assets	(1,438		)	(845	)	(931	)
Fair value of plan assets at end of year	$	11,072		12,571		12,346

Schedule of gross notional exposure of the derivative instruments directly held by the plans

The gross notional exposure of the derivative instruments directly held by the plans is shown below. The notional amount of the derivatives corresponds to market exposure but does not represent an actual cash investment.

	Gross Notional Exposure
	Pension Plans			Post-Retirement Benefit Plans
	Years Ended December 31,
	2015		2014	2015	2014
	(Dollars in millions)
Derivative instruments:
Exchange-traded U.S. equity futures	$	79	134	—	7
Exchange-traded Treasury and other interest rate futures	1,767		2,451	—	—
Interest rate swaps	550		579	—	—
Credit default swaps	189		382	—	—
Foreign exchange forwards	992		1,195	—	13
Options	285		529	—	—

Schedule of the unfunded status of the benefit plans

The following table presents the unfunded status of the pensions and post-retirement benefit plans:

	Pension Plans					Post-Retirement Benefit Plans
	Years Ended December 31,					Years Ended December 31,
	2015			2014		2015		2014
	(Dollars in millions)
Benefit obligation	$	(13,349	)	(15,042	)	(3,567	)	(3,830	)
Fair value of plan assets	11,072			12,571		193		353
Unfunded status	(2,277		)	(2,471	)	(3,374	)	(3,477	)
Current portion of unfunded status	$	(5	)	(6	)	(135	)	(134	)
Non-current portion of unfunded status	$	(2,272	)	(2,465	)	(3,239	)	(3,343	)

Schedule of items not recognized as a component of net periodic benefits expense

The items not recognized as a component of net periodic benefits expense have been recorded on our consolidated balance sheets in accumulated other comprehensive loss:

	As of and for the Years Ended December 31,
	2014			Recognition of Net Periodic Benefits Expense		Deferrals		Net Change in AOCL		2015
	(Dollars in millions)
Accumulated other comprehensive loss:
Pension plans:
Net actuarial (loss) gain	$	(2,760	)	161		(258	)	(97	)	(2,857	)
Prior service (cost) benefit	(32		)	5		99		104		72
Deferred income tax benefit (expense)	1,072			(63	)	61		(2	)	1,070
Total pension plans	(1,720		)	103		(98	)	5		(1,715	)
Post-retirement benefit plans:
Net actuarial (loss) gain	(277		)	—		130		130		(147	)
Prior service (cost) benefit	(166		)	19		—		19		(147	)
Deferred income tax benefit (expense)	171			(7	)	(50	)	(57	)	114
Total post-retirement benefit plans	(272		)	12		80		92		(180	)
Total accumulated other comprehensive loss	$	(1,992	)	115		(18	)	97		(1,895	)

Schedule of estimated items to be recognized in 2013 as a component of net periodic benefit expense

The following table presents estimated items to be recognized in 2016 as a component of net periodic benefit expense of the pension, non-qualified pension and post-retirement benefit plans:

	Pension Plans			Post-Retirement Plans
	(Dollars in millions)
Estimated recognition of net periodic benefit (cost)/income in 2016:
Net actuarial loss	$	(168	)	—
Prior service (cost)/income	8			(20	)
Deferred income tax benefit	61			8
Estimated net periodic benefit expense to be recorded in 2016 as a component of other comprehensive income (loss)	$	(99	)	(12	)

Pension Plan

Employee Benefits

Schedule of components of net periodic pension income and post-retirement benefit expense

Net periodic (income) expense for our qualified and non-qualified pension plans includes the following components:

	Pension Plans Years Ended December 31,
	2015			2014		2013
	(Dollars in millions)
Service cost	$	83		77		91
Interest cost	568			602		544
Expected return on plan assets	(898		)	(891	)	(896	)
Settlements	—			63		—
Recognition of prior service cost	5			5		5
Recognition of actuarial loss	161			22		84
Net periodic pension benefit income	$	(81	)	(122	)	(172	)

Schedule of change in benefit obligation

The following tables summarize the change in the benefit obligations for the pension and post-retirement benefit plans:

	Pension Plans Years Ended December 31,
	2015			2014		2013
	(Dollars in millions)
Change in benefit obligation
Benefit obligation at beginning of year	$	15,042		13,401		14,881
Service cost	83			77		91
Interest cost	568			602		544
Plan amendments	(100		)	4		—
Actuarial loss (gain)	(800		)	2,269		(1,179	)
Settlements	—			(460	)	—
Benefits paid by company	(6		)	(6	)	(5	)
Benefits paid from plan assets	(1,438		)	(845	)	(931	)
Benefit obligation at end of year	$	13,349		15,042		13,401

Schedule of change in plan assets

	Post-Retirement Benefit Plans Years Ended December 31,
	2015			2014		2013
	(Dollars in millions)
Change in plan assets
Fair value of plan assets at beginning of year	$	353		535		626
Return on plan assets	3			37		45
Benefits paid from plan assets	(163		)	(219	)	(136	)
Fair value of plan assets at end of year	$	193		353		535

Schedule of fair value of the plans' assets by asset category

The tables below present the fair value of plan assets by category and the input levels used to determine those fair values at December 31, 2015. It is important to note that the asset allocations do not include market exposures that are gained with derivatives. Investments include dividend and interest receivables, pending trades and accrued expenses.

	Fair Value of Pension Plan Assets at December 31, 2015
	Level 1		Level 2		Level 3	Total
	(Dollars in millions)
Investment grade bonds (a)	$	841	1,045		—	$	1,886
High yield bonds (b)	—		544		13	557
Emerging market bonds (c)	208		232		1	441
Convertible bonds (d)	—		2		—	2
U.S. stocks (f)	1,201		—		—	1,201
Non-U.S. stocks (g)	1,127		1		—	1,128
Multi-asset strategies (m)	376		—		—	376
Derivatives (n)	2		(6	)	—	(4		)
Cash equivalents and short-term investments (o)	—		192		—	192
Total investments, excluding investments valued at NAV	$	3,755	2,010		14	5,779
Investments valued at NAV						5,293
Total pension plan assets						$	11,072

The tables below present the fair value of plan assets by category and the input levels used to determine those fair values at December 31, 2014. It is important to note that the asset allocations do not include market exposures that are gained with derivatives. Investments include dividend and interest receivable, pending trades and accrued expenses.

	Fair Value of Pension Plan Assets at December 31, 2014
	Level 1		Level 2	Level 3	Total
	(Dollars in millions)
Investment grade bonds (a)	$	1,068	1,278	—	$	2,346
High yield bonds (b)	—		647	7	654
Emerging market bonds (c)	208		407	—	615
Convertible bonds (d)	—		4	—	4
U.S. stocks (f)	1,389		1	—	1,390
Non-U.S. stocks (g)	1,169		1	—	1,170
Derivatives (n)	2		15	—	17
Cash equivalents and short-term investments (o)	—		626	—	626
Total investments, excluding investments valued at NAV	$	3,836	2,979	7	6,822
Investments valued at NAV					5,749
Total pension plan assets					$	12,571

Summary of changes in fair value of defined benefit plans' Level 3 assets

The table below presents a rollforward of the pension plan assets valued using Level 3 inputs:

	Pension Plan Assets Valued Using Level 3 Inputs
	High Yield Bonds			Emerging Market Bonds	Total
	(Dollars in millions)
Balance at December 31, 2013	$	—		—	—
Net transfers	6			—	6
Acquisitions	1			—	1
Dispositions	(3		)	—	(3	)
Actual return on plan assets:
Gains relating to assets sold during the year	4			—	4
(Losses) gains relating to assets still held at year-end	(1		)	—	(1	)
Balance at December 31, 2014	7			—	7
Net transfers	4			1	5
Acquisitions	4			—	4
Dispositions	(2		)	—	(2	)
Actual return on plan assets:
Gains relating to assets sold during the year	—			—	—
(Losses) gains relating to assets still held at year-end	—			—	—
Balance at December 31, 2015	$	13		1	14

Post-Retirement Benefit Plans

Employee Benefits

Schedule of effects of a 100 basis point change in assumed health care cost rates

A change of 100 basis points in the assumed initial health care cost trend rate would have had the following effects in 2015:

	100 Basis Points Change
	Increase		(Decrease)
	(Dollars in millions)
Effect on the aggregate of the service and interest cost components of net periodic post-retirement benefit expense (consolidated statement of operations)	$	3	(3	)
Effect on benefit obligation (consolidated balance sheet)	73		(68	)

Schedule of components of net periodic pension income and post-retirement benefit expense

Net periodic expense (income) for our post-retirement benefit plans includes the following components:

	Post-Retirement Plans Years Ended December 31,
	2015			2014		2013
	(Dollars in millions)
Service cost	$	24		22		24
Interest cost	140			159		140
Expected return on plan assets	(21		)	(33	)	(39	)
Recognition of prior service cost	19			20		—
Recognition of actuarial loss	—			—		4
Net periodic post-retirement benefit expense	$	162		168		129

Schedule of change in benefit obligation

	Post-Retirement Benefit Plans Years Ended December 31,
	2015			2014		2013
	(Dollars in millions)
Change in benefit obligation
Benefit obligation at beginning of year	$	3,830		3,688		4,075
Service cost	24			22		24
Interest cost	140			159		140
Participant contributions	57			69		96
Plan amendments	—			23		141
Direct subsidy receipts	8			9		13
Actuarial loss (gain)	(148		)	245		(399	)
Benefits paid by company	(181		)	(166	)	(266	)
Benefits paid from plan assets	(163		)	(219	)	(136	)
Benefit obligation at end of year	$	3,567		3,830		3,688

Schedule of fair value of the plans' assets by asset category

	Fair Value of Post-Retirement Plan Assets at December 31, 2015
	Level 1		Level 2	Level 3	Total
	(Dollars in millions)
Investment grade bonds (a)	$	2	1	—	$	3
High yield bonds (b)	—		1	—	1
U.S. stocks (f)	16		—	—	16
Non-U.S. stocks (g)	12		—	—	12
Emerging market stocks (h)	4		—	—	4
Cash equivalents and short-term investments (o)	—		4	—	4
Total investments, excluding investments valued at NAV	$	34	6	—	40
Investments valued at NAV					153
Total post-retirement plan assets					$	193

	Fair Value of Post-Retirement Plan Assets at December 31, 2014
	Level 1		Level 2	Level 3	Total
	(Dollars in millions)
Investment grade bonds (a)	$	5	1	—	$	6
High yield bonds (b)	—		1	—	1
U.S. stocks (f)	35		—	—	35
Non-U.S. stocks (g)	33		—	—	33
Emerging market stocks (h)	6		—	—	6
Cash equivalents and short-term investments (o)	—		8	—	8
Total investments, excluding investments valued at NAV	$	79	10	—	89
Investments valued at NAV					264
Total post-retirement plan assets					$	353

Pension, Supplemental And Other Postretirement Benefit Plans [Member]

Employee Benefits

Schedule of fair value of the plans' assets by asset category

The table below presents the fair value of plan assets valued at NAV by category for our pension and post-retirement plans at December 31, 2015 and 2014. See Note 1 - Basis of Presentation and Summary of Significant Accounting Policies for additional information regarding the 2015 adoption of ASU 2015-07.

	Fair Value of Plan Assets Valued at NAV
	Pension Plans at December 31,			Post-Retirement Benefit Plans at December 31,
	2015		2014	2015	2014
	(Dollars in millions)
Investment grade bonds (a)	$	115	148	35	71
High yield bonds (b)	512		860	1	14
Emerging market bonds (c)	9		27	—	—
Convertible bonds (d)	—		10	—	—
Diversified strategies (e)	516		718	54	89
U.S. stocks (f)	70		86	—	—
Non-U.S. stocks (g)	289		384	—	—
Emerging market stocks (h)	64		102	—	—
Private equity (i)	526		673	21	28
Private debt (j)	371		394	2	3
Market neutral hedge funds (k)	825		1,026	17	25
Directional hedge funds (k)	594		558	1	1
Real estate (l)	968		699	20	28
Multi-asset strategies (m)	386		—	—	—
Cash equivalents and short-term investments (o)	48		64	2	5
Total investments valued at NAV	$	5,293	5,749	153	264