Pension and Other Postretirement Plans (Obligations and Funded Status) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Pension Plans [Member]
Change in projected benefit obligations:
Projected benefit obligations at beginning of year	$ 21,187	$ 23,535
Service cost	168	190	174
Interest cost	958	873	928
Actuarial loss (gain)	(2,357)	2,088
Benefits paid	(1,342)	(1,323)
Projected benefit obligations at end of year	23,328	21,187	23,535
Change in plan assets:
Fair value at beginning of year	18,908	16,813
Actual return on plan assets	1,747	2,967
Contributions	333	451
Benefits paid	(1,342)	(1,323)
Fair value at end of year	19,646	18,908	16,813
Funded status at end of year	(3,682)	(2,279)
Chairman and President Non-Qualified Defined Benefit Plans [Member]
Change in projected benefit obligations:
Projected benefit obligations at beginning of year	19,870	22,525
Service cost	294	177	168
Interest cost	1,003	801	912
Actuarial loss (gain)	4,960	(1,652)
Benefits paid	(1,982)	(1,981)
Projected benefit obligations at end of year	24,145	19,870	22,525
Change in plan assets:
Fair value at beginning of year	0	0
Contributions	1,982	1,981
Benefits paid	(1,982)	(1,981)
Fair value at end of year	0	0	0
Funded status at end of year	(24,145)	(19,870)
Defined Benefit Postretirement Healthcare Plans [Member]
Change in projected benefit obligations:
Projected benefit obligations at beginning of year	2,725	3,482
Interest cost	111	117	129
Actuarial loss (gain)	(107)	827
Benefits paid	(53)	(47)
Projected benefit obligations at end of year	2,890	2,725	3,482
Change in plan assets:
Fair value at beginning of year	0	0
Contributions	53	47
Benefits paid	(53)	(47)
Fair value at end of year	0	0	0
Funded status at end of year	$ (2,890)	$ (2,725)