Annuity equivalent of contribution to defined contribution plan deducted from monthly benefit of basic retirement plan.

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- Definition

Defined benefit plan unrecognized service cost amortization period.

+ Details

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- Definition

Employee Contribution Percentage

+ Details

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- Definition

Employees Additional Eligible Automatic Contribution

+ Details

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- Definition

Employees age limit to be eligible for participation in defined contribution plan.

+ Details

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- Definition

Employees Eligible Automatic Contribution

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- Definition

Increased annuity equivalent of contribution to defined contribution plan deducted from monthly benefit of basic retirement plan.

+ Details

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- Definition

Number of supplemental non qualified retirement plans.

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- Definition

Percent of employee contribution matched by corporation

+ Details

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- Definition

pre medicare eligible postretirement medical insurance plan employees age limit to be eligible for employer-paid coverage.

+ Details

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- Definition

Pre medicare eligible postretirement medical insurance plan maximum age limit.

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- Definition

Pre Medicare eligible postretirement medical insurance plan minimum age limit.

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- Definition

Amount related to the pretax cost of benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation, which has not yet been recognized as components of net periodic benefit cost.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 87
-Paragraph 264

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph i

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 158
-Paragraph 7
-Subparagraph c

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 106
-Paragraph 518

+ Details

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- Definition

The amounts in accumulated other comprehensive income related to prior service cost or credit expected to be recognized as components of net periodic benefit cost over the next fiscal year that follows the most recent annual statement of financial position presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph s

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 158
-Paragraph 7
-Subparagraph d

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 11

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Retirement and Other Postretirement Benefit Plans (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	1 Months Ended		6 Months Ended		12 Months Ended			24 Months Ended
	Jan. 31, 2011	Jan. 31, 2008	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2008	Dec. 31, 2011	Jan. 07, 2007	Jan. 01, 2007
Retirement And Other Postretirement Benefit Plans
Net unrecognized service credit									$ 14,079
Number of years for which net unrecognized service credit is being amortized									13.5
Unrecognized prior service credit included in income						10,543
Number of supplemental non-qualified retirement plans sponsored by the corporation			2
Percent of Employer Match					100.00%	50.00%
Employee Contribution Percentage					4.00%			6.00%
Annuity equivalent of contribution to defined contribution plan deducted from monthly benefit of basic retirement plan			3.00%
Employees' required age to be eligible for participation in defined contribution plan, minimum			21
Increase in annuity equivalent of contribution to defined contribution plan deducted from monthly benefit of basic retirement plan for full-time employees		4.00%
Additional automatic contribution increase, performance goals, percentage							2.00%
Contribution expense of the corporation			$ 4,069	$ 2,500
Automatic contribution increase available under contribution method each calendar year, percentage	3.00%
Pre-medicare eligible postretirement medical insurance plan minimum age limit			62
Pre-medicare eligible postretirement medical insurance plan employees age limit to be eligible for employer-paid coverage										60 or older
Pre-medicare eligible postretirement medical insurance plan maximum age limit			65