Employee Benefit Plans (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Defined pension plan benefits
Components of net periodic benefit cost
Service cost – benefits earned during the year	$ 7	$ 13
Interest cost on projected benefit obligations	494	452
Expected return on plan assets	(713)	(695)
Amortization of prior service cost	0	0
Amortization of net loss	153	215
Net periodic benefit cost (income)	(59)	(15)
Other postretirement benefits
Components of net periodic benefit cost
Service cost – benefits earned during the year	36	42
Interest cost on projected benefit obligations	73	66
Expected return on plan assets	0	0
Amortization of prior service cost	40	40
Amortization of net loss	0	3
Net periodic benefit cost (income)	$ 149	$ 151