Defined Pension Plans (Schedule of Net Periodic Pension Costs) (Details) (USD $)
In Thousands, unless otherwise specified |
6 Months Ended | 12 Months Ended |
---|---|---|
Jun. 30, 2013
|
Dec. 31, 2012
|
|
Defined Benefit Pension Plan [Member]
|
||
Service cost - benefits earned during the year | $ 3,519 | $ 2,799 |
Interest cost on projected benefit obligation | 2,821 | 2,570 |
Expected return on plan assets | (4,472) | (3,967) |
Net amortization and deferral | 1,849 | 1,473 |
Net periodic pension cost | 3,717 | 2,875 |
Unfunded Supplemental Executive Retirement Plan [Member]
|
||
Service cost - benefits earned during the year | 144 | 115 |
Interest cost on projected benefit obligation | 335 | 307 |
Net amortization and deferral | 551 | 360 |
Net periodic pension cost | $ 1,030 | $ 782 |