Redeemable Noncontrolling Interests (Narrative) (Details) (USD $) In Millions, unless otherwise specified	1 Months Ended	12 Months Ended	1 Months Ended
Mar. 31, 2013 Additional Paid-In Capital [Member]	Dec. 31, 2011 Canadian Joint Venture [Member]	Mar. 31, 2013 Central American Joint Venture [Member]
Noncontrolling Interest [Line Items]
Acquired noncontrolling interest		$ 0.7	$ 6.0
Acquired additional non-controlling interest		4.60%	10.00%
Ownership interest after acquisition		100.00%	100.00%
Adjusted non-controlling interest	$ 5.7

The cash outflow associated with the investment in or advances to an entity in which the reporting entity shares control of the entity with another party or group.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration