Subsequent Events (Details) (Subsequent Event [Member], USD $) In Millions, except Per Share data, unless otherwise specified	0 Months Ended
Jan. 29, 2015	Feb. 17, 2015
Subsequent Event [Line Items]
Cash dividend declared by the Company		$ 0.40us-gaap_DividendsPayableAmountPerShare
Longtrain Leasing III [Member] \| Private Placement [Member]
Subsequent Event [Line Items]
Proceeds from Issuance of Private Placement	$ 625.5
Debt Instrument, Interest Rate, Increase (Decrease)	5.00%
Longtrain Leasing III [Member] \| Private Placement [Member] \| Class A-1 Notes [Member] \| Secured Debt [Member]
Subsequent Event [Line Items]
Proceeds from Issuance of Private Placement	250.0
Debt Instrument, Interest Rate, Stated Percentage	2.98%
Longtrain Leasing III [Member] \| Private Placement [Member] \| Class A-2 Notes [Member] \| Secured Debt [Member]
Subsequent Event [Line Items]
Proceeds from Issuance of Private Placement	$ 375.5
Debt Instrument, Interest Rate, Stated Percentage	4.06%

Incremental percentage increase (decrease) in the stated rate on a debt instrument.

No definition available.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

+ Details

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- Definition

The cash inflow associated with the amount received from entity's raising of capital via private rather than public placement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585

+ Details

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- Details

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- Details

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