Subsequent Event (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	0 Months Ended
Mar. 31, 2013 stage	May 02, 2013 Subsequent Event term sqft
Subsequent Event [Line Items]
Lease term		11 years
Lease area		85,000
Rent expense		$ 3.5
Number of extensions		2
Extension term		5 years
Number of stages for termination of lease	3
Loss on contract termination	$ 6.6

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