Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41499-112717

Name:	us-gaap_OperatingLeasesRentExpenseNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

TRANSACTIONS WITH AFFILIATES (Details) (USD $) In Thousands, unless otherwise specified	1 Months Ended	12 Months Ended
	Jul. 31, 2009 item	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
TRANSACTIONS WITH AFFILIATES
Rental expense		$ 2,574	$ 2,567	$ 2,599
Affiliated entities
TRANSACTIONS WITH AFFILIATES
Number of renewal options	2
Term of each renewal option	5 years
Rental expense		$ 1,377	$ 1,350	$ 1,353