Share-Based Payments (Details)	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Schedule of stock option and restricted stock unit grants
Stock options		124,000
Market stock units [Member]
Schedule of stock option and restricted stock unit grants
Restricted stock units	373,000	334,000
Cash settled performance shares [Member]
Schedule of stock option and restricted stock unit grants
Restricted stock units	483,000	373,000
Time Vested Restricted Stock Units [Member]
Schedule of stock option and restricted stock unit grants
Restricted stock units	1,303,000	1,700,000
Performance vested restricted stock units settled in shares [Member]
Schedule of stock option and restricted stock unit grants
Restricted stock units	1,000	4,000

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

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