Fair Value Measurements (Details 4) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Financial liability measured at fair value on a recurring basis
Interest rate swap	$ 1,607
Quoted Prices in Active Markets for Identical (Level 1) [Member]
Financial liability measured at fair value on a recurring basis
Interest rate swap
Significant Other Observable Inputs (Level 2) [Member]
Financial liability measured at fair value on a recurring basis
Interest rate swap	1,607
Significant Unobservable Inputs (Level 3) [Member]
Financial liability measured at fair value on a recurring basis
Interest rate swap
Loss for Year [Member]
Financial liability measured at fair value on a recurring basis
Interest rate swap

Fair value as of the balance sheet date of all interest rate derivative liabilities designated as cash flow hedging instruments.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624163-113959

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 17

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

Name:	us-gaap_InterestRateCashFlowHedgeLiabilityAtFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant