Leases (Future Minimum Rental Payments For Operating Leases) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014
Summary of future minimum rental payments for operating leases [Abstract]
2015	$ 14,131
2016	13,927
2017	13,861
2018	12,783
2019	3,508
Thereafter	3,187
Total Future Minimum Payments	61,397
Vessels [Member]
Summary of future minimum rental payments for operating leases [Abstract]
2015	12,499
2016	12,499
2017	12,500
2018	11,735
2019	2,842
Total Future Minimum Payments	52,075
Other Leases [Member]
Summary of future minimum rental payments for operating leases [Abstract]
2015	1,632
2016	1,428
2017	1,361
2018	1,048
2019	666
Thereafter	3,187
Total Future Minimum Payments	$ 9,322

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

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

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

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

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

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

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

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Amount of required minimum rental payments maturing after the fifth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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