Share-Based Compensation (Summary of the Stock Options Granted) (Details)	3 Months Ended	6 Months Ended
Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Shares, Granted	2,700	205,489	238,050
Three Year Vesting [Member]
Shares, Granted	2,700	200,200	238,050
One Year Vesting [Member]
Shares, Granted		5,289

Net number of share options (or share units) granted during the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph b(1)(d)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod
Namespace Prefix:	us-gaap
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration