Retirement Plans (Schedule Of Net Periodic Benefit Costs) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
UNITED STATES
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 9	$ 9	$ 18	$ 19
Interest cost	186	185	372	370
Expected return on plan assets	(179)	(204)	(358)	(408)
Recognized net actuarial loss	(69)	(69)	(138)	(138)
Net periodic pension cost	85	59	170	119
UNITED KINGDOM
Defined Benefit Plan Disclosure [Line Items]
Interest cost	75	77	150	153
Expected return on plan assets	(84)	(83)	(168)	(166)
Amortization of prior service cost and transition amount	5	5	10	10
Recognized net actuarial loss	(39)	(59)	(78)	(117)
Net periodic pension cost	$ 35	$ 58	$ 70	$ 114