Condensed Consolidating Financial Statements (Details Textual) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Condensed Financial Statements, Captions [Line Items]
Net holding gains, tax expense	$ 53	$ 0	$ 585	$ 0
Reclassification of prior service credit recorded to net income, tax expense	56	57	113	114
Reclassification of net actuarial loss recorded to net income, tax benefit	595	620	1,191	1,242
Unrealized foreign currency translation (losses) gains, tax (benefit) expense	(1,127)	205	125	648
Condensed Consolidating Financial Statements (Textual) [Abstract]
Percentage ownership in subsidiary for unconditional guarantee of debt securities			100.00%
Parent [Member]
Condensed Financial Statements, Captions [Line Items]
Net holding gains, tax expense	53		585
Reclassification of prior service credit recorded to net income, tax expense	56	57	113	114
Reclassification of net actuarial loss recorded to net income, tax benefit	595	620	1,191	1,242
Unrealized foreign currency translation (losses) gains, tax (benefit) expense	(1,127)	205	125	648
Subsidiary Guarantors [Member]
Condensed Financial Statements, Captions [Line Items]
Net holding gains, tax expense	53		585
Reclassification of prior service credit recorded to net income, tax expense	56	57	113	114
Reclassification of net actuarial loss recorded to net income, tax benefit	595	620	1,191	1,242
Unrealized foreign currency translation (losses) gains, tax (benefit) expense	(1,127)	205	125	648
Non-Guarantors [Member]
Condensed Financial Statements, Captions [Line Items]
Unrealized foreign currency translation (losses) gains, tax (benefit) expense	(1,127)	205	125	648
Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Net holding gains, tax expense	(53)		(585)
Reclassification of prior service credit recorded to net income, tax expense	(56)	(57)	(113)	(114)
Reclassification of net actuarial loss recorded to net income, tax benefit	(595)	(620)	(1,191)	(1,242)
Unrealized foreign currency translation (losses) gains, tax (benefit) expense	$ 1,127	$ (205)	$ (125)	$ (648)

Tax effect of the income statement impact of the reclassification adjustment for prior service costs recognized as a component of net period benefit cost.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 130

-Paragraph 25

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 87

-Paragraph 25

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 38

-Subparagraph c(3)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e640-108580

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 158

-Paragraph 7

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

- Definition

Tax effect, net of reclassification adjustments, of the change in the balance sheet adjustment that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency of the reporting entity. Also includes the following: gain (loss) on foreign currency forward exchange contracts; foreign currency transactions designated as hedges of net investment in a foreign entity and intercompany foreign currency transactions that are of a long-term nature, when the entities to the transaction are consolidated, combined, or accounted for by the equity method in the reporting enterprise's financial statements; and gain (loss) on a derivative instrument or nonderivative financial instrument that may give rise to a foreign currency transaction gain (loss) that has been designated and qualified as a hedging instrument for hedging of the foreign currency exposure of a net investment in a foreign operation.

+ References+ Details

- Definition

Tax effect of unrealized holding gain (loss) before reclassification adjustments and transfers on available-for-sale securities.

+ References+ Details