Retirement And Other Employee Benefits (Summary Of Change In Fair Value Financial Asset) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	$ 879,211	$ 786,750
Fair value of plan assets at end of year	832,686	879,211	$ 786,750
Pension Benefits
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	879,211	786,750	704,976
Actual return on plan assets and plan expenses still held at the reporting date	(5,458)	102,628	64,641
Fair value of plan assets at end of year	832,686	879,211	786,750
Retirement Health Benefits
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	50,068	46,971	45,651
Actual return on plan assets and plan expenses still held at the reporting date	(291)	5,403	3,234
Fair value of plan assets at end of year	46,856	50,068	$ 46,971
Level 3 | Pension Benefits
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	67,746
Purchases	1,403
Refund of capital	(86)
Actual return on plan assets and plan expenses still held at the reporting date	(1,092)
Fair value of plan assets at end of year	67,971	67,746
Level 3 | Retirement Health Benefits
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	3,858
Purchases	79
Refund of capital	(5)
Actual return on plan assets and plan expenses still held at the reporting date	(107)
Fair value of plan assets at end of year	$ 3,825	$ 3,858