Leases (Schedule of Lease Minimum Payments) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014
Property Subject to Operating Lease [Member]
lease payments [Line Items]
Operating Leases, Future Minimum Payments Due, Next Twelve Months	$ 25,685
Operating Leases, Future Minimum Payments, Due in Two Years	19,242
Operating Leases, Future Minimum Payments, Due in Three Years	17,065
Operating Leases, Future Minimum Payments, Due in Four Years	6,334
Operating Leases, Future Minimum Payments, Due in Five Years	3,370
Operating Leases, Future Minimum Payments, Due Thereafter	11,880
Operating Leases, Future Minimum Payments Due	83,576
Royalty Agreements [Member]
lease payments [Line Items]
Operating Leases, Future Minimum Payments Due, Next Twelve Months	14,587
Operating Leases, Future Minimum Payments, Due in Two Years	18,632
Operating Leases, Future Minimum Payments, Due in Three Years	17,932
Operating Leases, Future Minimum Payments, Due in Four Years	17,584
Operating Leases, Future Minimum Payments, Due in Five Years	13,875
Operating Leases, Future Minimum Payments, Due Thereafter	83,282
Operating Leases, Future Minimum Payments Due	$ 165,892

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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 20

-Section 50

-Paragraph 2

-Subparagraph (a)

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

Reference 2: 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

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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