New Accounting Pronouncements (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
Jun. 30, 2011	Jan. 02, 2011
New Accounting Pronouncements
Number of separate statements in which the entity is required to present comprehensive income	2
Increase in retained earnings due to adoption of new accounting pronouncement		$ 2.9

The amount of the cumulative effect on retained earnings net of related income tax effect.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-SubTopic 10
-Topic 250
-URI http://asc.fasb.org/extlink&oid=6801783&loc=d3e22663-107794

Name:	us-gaap_CumulativeEffectOnRetainedEarningsNetOfTax
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant