Net Income or Loss Per Share (Details) (SARs)	3 Months Ended	9 Months Ended
Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2012
SARs
Share-based Compensation
Exercised in period (in shares)	253,000	0	0

Number of non-option equity instruments exercised by participants.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iv)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercised
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration