Consolidated Statements Of Changes In Equity (Parenthetical) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Statement of Stockholders' Equity [Abstract]
Preferred dividends on subsidiaries' preferred stock	$ 3.2us-gaap_DividendsPreferredStockCash	$ 3.2us-gaap_DividendsPreferredStockCash

Amount of paid and unpaid preferred stock dividends declared with the form of settlement in cash.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 405

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817

Name:	us-gaap_DividendsPreferredStockCash
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration