CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) [Abstract]
Net income	$ 13,478	$ 4,639
Other comprehensive income (loss), net of tax
Net change in unrealized gain on investment securities	(3,480)	991
Net change in unrealized loss on derivatives	(572)	(1,116)
Minimum pension liability adjustment	589	555
Other comprehensive income (loss), net of tax	(3,463)	430
Comprehensive income	$ 10,015	$ 5,069

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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-Name Accounting Standards Codification

-Topic 220

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-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 30

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-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph A5

-Appendix A

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-Name Accounting Research Bulletin (ARB)

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Comprehensive Income

-URI http://asc.fasb.org/extlink&oid=6508144

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Net Income

-URI http://asc.fasb.org/extlink&oid=6518256

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-Name Accounting Standards Codification

-Glossary Other Comprehensive Income

-URI http://asc.fasb.org/extlink&oid=6519514

+ Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

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-Appendix A

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-Glossary Other Comprehensive Income

-URI http://asc.fasb.org/extlink&oid=6519514

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-Glossary Net Income

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-Topic 944

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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-Section 03

-Paragraph 19

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-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 20

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+ Details

- Definition

This element represents Other Comprehensive Income or Loss, Net of Tax, for the period attributable to the parent entity. Includes deferred gains or losses on qualifying hedges, unrealized holding gains or losses on available-for-sale securities, minimum pension liability, and cumulative translation adjustment.

+ References

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+ Details

- Definition

The after-tax amount of the change in the additional pension liability not yet recognized pursuant to FAS 87 par 37 and 38 as a net periodic pension cost. If the additional pension liability required to be recognized exceeds the unrecognized prior service costs, then the excess (which is the net loss not yet recognized as net periodic pension cost) is to be recorded as a reduction of other comprehensive income, before adjusting for tax effects. If in a subsequent measurement, the amount of minimum liability is eliminated or adjusted, this adjustment is offset against other comprehensive income in Accumulated Comprehensive Income. This line also includes changes in an entity's share of an equity investee's Increase or Decrease in additional pension liability not yet recognized as a net periodic pension cost. Eliminated upon adoption of FAS 158.

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-Name Regulation S-X (SX)

-Number 210

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- Definition

Change in accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges, net of tax effect. The after tax effect change includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

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Appreciation or loss in value (before reclassification adjustment) of the total of unsold securities during the period being reported on, net of tax. Reclassification adjustments include: (1) the unrealized holding gain (loss), net of tax, at the date of the transfer for a debt security from the held-to-maturity category transferred into the available-for-sale category. Also includes the unrealized gain (loss) at the date of transfer for a debt security from the available-for-sale category transferred into the held-to-maturity category; (2) the unrealized gains (losses) realized upon the sale of securities, after tax; and (3) the unrealized gains (losses) realized upon the write-down of securities, after tax.

+ References

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+ Details