Accrued Liabilities (Details 2) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Accrued Liabilities
Accrued realized losses on cash flow interest rate swaps	$ 5.1	$ 10.4
Other accruals	$ 3.5	$ 3.7

Carrying value as of the balance sheet date of obligations incurred through that date and payable arising from transactions not otherwise specified in the taxonomy. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 9

-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e7018-107765

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Current Liabilities

-URI http://asc.fasb.org/extlink&oid=6509677

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6911-107765

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section 45

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6935-107765

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.20)

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

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