Employee Benefit Plans Expected benefits (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2012	$ 2,341
2013	2,476
2014	2,602
2015	2,844
2016	3,090
2017-2021	19,757
Defined Benefit Plan Expected Future Benefit Payments	33,110
Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2012	483
2013	483
2014	478
2015	498
2016	517
2017-2021	2,772
Defined Benefit Plan Expected Future Benefit Payments	$ 5,231

The amount of the aggregate benefits expected to be paid in the five fiscal years thereafter (the aggregate amount of benefits expected to be paid in years 6 through 10 after the date of the latest statement of financial position).

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

-Subparagraph f

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e1928-114920

Name:	us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsInFiveFiscalYearsThereafter
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant