Leased Properties (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Leases, Operating [Abstract]
Operating lease, rental expense	$ 1.5us-gaap_OperatingLeasesRentExpenseNet	$ 1.1us-gaap_OperatingLeasesRentExpenseNet	$ 0.9us-gaap_OperatingLeasesRentExpenseNet
2015	1.4
2016	1.4
2017	1.3
2018	0.7
2019	0.2
Total	$ 5.0

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

-Section 55

-Paragraph 40

-Subparagraph (Note 3)

-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717

+ Details

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- Definition

Amount of required minimum rental payments maturing in the fifth rolling twelve months following the latest balance sheet presented for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

No definition available.

+ Details

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- Definition

Amount of required minimum rental payments maturing in the forth rolling twelve months following the latest balance sheet presented for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

No definition available.

+ Details

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- Definition

Amount of required minimum rental payments maturing in the third rolling twelve months following the latest balance sheet presented for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

No definition available.

+ Details

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- Definition

Amount of required minimum rental payments maturing in the second rolling twelve months following the latest balance sheet presented for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

No definition available.

+ Details

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- Definition

Amount of required minimum rental payments maturing in the next rolling twelve months following the latest balance sheet presented for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

No definition available.

+ Details

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- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41499-112717

+ Details

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Balance Type:	debit
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