Employee Benefit Plans (Changes In The Projected Benefit Obligation, The Fair Value Of Plan Assets And The Determination Of The Amounts Recognized) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Fair value of pension plan assets at ending of year	$ 1,701,694	$ 1,438,865
Long-term assets	18,110	15,018
Qualified Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation at beginning of year	1,523,531	1,680,603
Interest cost on projected benefit obligation	75,030	70,022	70,168
Actuarial loss (gain)	136,142	(238,037)	(720)
Plan settlement	(36,237)	0
Actuarial loss (gain)	254,379	(177,347)
Benefits paid	(54,536)	(49,747)
Projected and accumulated benefit obligation at end of year	1,762,167	1,523,531	1,680,603
Fair value of pension plan assets at beginning of year	1,438,865	1,281,261
Actual return on plan assets	211,322	152,014
Con-way contributions	142,280	55,337
Plan settlement	(36,237)	0
Fair value of pension plan assets at ending of year	1,701,694	1,438,865	1,281,261
Funded status of the plans	(60,473)	(84,666)
Long-term assets	18,110	15,018
Current liabilities	0	0
Long-term liabilities	(78,583)	(99,684)
Net amount recognized	(60,473)	(84,666)
Projected and accumulated benefit obligation	1,740,798	1,502,541
Fair value of plan assets	1,622,215	1,402,857
Discount rate	4.20%	5.05%
Non-Qualified Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation at beginning of year	70,814	78,218
Interest cost on projected benefit obligation	3,451	3,213	3,438
Actuarial loss (gain)	9,182	(5,508)	3,574
Plan settlement	0	0
Actuarial loss (gain)	9,182	(5,508)
Benefits paid	(5,101)	(5,109)
Projected and accumulated benefit obligation at end of year	78,346	70,814	78,218
Fair value of pension plan assets at beginning of year	0	0
Actual return on plan assets	0	0
Con-way contributions	5,101	5,109
Plan settlement	0	0
Fair value of pension plan assets at ending of year	0	0	0
Funded status of the plans	(78,346)	(70,814)
Long-term assets	0	0
Current liabilities	(5,148)	(5,145)
Long-term liabilities	(73,198)	(65,669)
Net amount recognized	(78,346)	(70,814)
Projected and accumulated benefit obligation	78,346	70,814
Fair value of plan assets	0	0
Discount rate	4.20%	5.05%
Postretirement Medical Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation at beginning of year	61,917	102,291
Service cost	950	1,459	1,679
Interest cost on projected benefit obligation	2,734	3,434	4,318
Plan amendments	0	(19,243)
Actuarial loss (gain)	8,918	(21,143)	1,979
Participant contributions	2,191	2,009
Benefits paid	(5,677)	(6,890)
Projected and accumulated benefit obligation at end of year	71,033	61,917	102,291
Funded status of the plans	(71,033)	(61,917)
Current liabilities	(4,389)	(4,462)
Long-term liabilities	(66,644)	(57,455)
Net amount recognized	$ (71,033)	$ (61,917)
Discount rate	3.75%	4.50%