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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

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-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.

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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.

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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.

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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.

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

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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

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OPERATING LEASES AND COMMITMENTS (Details) (USD $)	12 Months Ended
OPERATING LEASES AND COMMITMENTS (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating Leases and Commitments
Rental expense	$ 30,200,000us-gaap_OperatingLeasesRentExpenseNet	$ 24,100,000us-gaap_OperatingLeasesRentExpenseNet	$ 20,300,000us-gaap_OperatingLeasesRentExpenseNet
Future minimum rental commitments for all noncancelable operating leases
2015	13,969,000
2016	10,759,000
2017	8,669,000
2018	7,165,000
2019	5,636,000
Thereafter	11,225,000
Total	57,423,000
Land and structures (terminals)
Future minimum rental commitments for all noncancelable operating leases
2015	13,071,000
2016	10,554,000
2017	8,550,000
2018	7,086,000
2019	5,573,000
Thereafter	11,225,000
Total	56,059,000
Service, office, and other equipment
Future minimum rental commitments for all noncancelable operating leases
2015	898,000
2016	205,000
2017	119,000
2018	79,000
2019	63,000
Total	$ 1,364,000