Supplemental Executive Retirement Plan (Details) (USD $) In Thousands | 3 Months Ended | 9 Months Ended | |||
|---|---|---|---|---|---|
Sep. 30, 2011 | Sep. 30, 2010 | Sep. 30, 2011 | Sep. 30, 2010 | Dec. 31, 2010 | |
| Supplemental Executive Retirement Plan Disclosure | |||||
| Balance in the Rabbi Trust at the end of the period | $ 5,123 | $ 5,123 | $ 5,122 | ||
Supplemental Executive Retirement Plan (SERP) | |||||
| Supplemental Executive Retirement Plan Disclosure | |||||
| Balance in the Rabbi Trust at the end of the period | 5,100 | 5,100 | 5,100 | ||
| Components of the periodic benefit cost | |||||
| Service cost | 1,079 | 988 | 3,176 | 2,700 | |
| Interest cost | 352 | 248 | 1,004 | 635 | |
| Amortization of prior service costs | 207 | 90 | 566 | 163 | |
| Amortization of net actuarial loss | 20 | 32 | 71 | 87 | |
| Net pension expense | $ 1,658 | $ 1,358 | $ 4,817 | $ 3,585 | |
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- Definition The amount of gains or losses recognized in net periodic benefit cost. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The amount of the prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
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- Definition The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The noncurrent cash, cash equivalents and investments that is restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits classified as long-term; that is not expected to be released from such existing restrictions within one year of the balance sheet date or operating cycle, whichever is longer. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. Includes noncurrent cash equivalents and investments that are similarly restricted as to withdrawal, usage or disposal.
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