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Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 2 -Article 5 false 6 General and administrative 2 us-gaap_GeneralAndAdministrativeExpense us-gaap true debit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 18199000 18199 false false false 2 false true false false 9507000 9507 false false false 3 false true false false 53393000 53393 false false false 4 false true false false 49653000 49653 false false false xbrli:monetaryItemType monetary The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line. No authoritative reference available. false 7 Depreciation and amortization 2 us-gaap_DepreciationAndAmortization us-gaap true debit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 20856000 20856 false false false 2 false true false false 19590000 19590 false false false 3 false true false false 65538000 65538 false false false 4 false true false false 72325000 72325 false false false xbrli:monetaryItemType monetary The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production. 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No authoritative reference available. true 10 Total operating expenses 2 us-gaap_OperatingExpenses us-gaap true debit duration No definition available. false false false false false false false false false false false totallabel false 1 false true false false 84807000 84807 false false false 2 false true false false 62271000 62271 false false false 3 false true false false 240317000 240317 false false false 4 false true false false 222522000 222522 false false false xbrli:monetaryItemType monetary Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense. No authoritative reference available. true 11 OPERATING INCOME 1 us-gaap_OperatingIncomeLoss us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 93213000 93213 false false false 2 false true false false 89057000 89057 false false false 3 false true false false 267459000 267459 false false false 4 false true false false 241985000 241985 false false false xbrli:monetaryItemType monetary The net result for the period of deducting operating expenses from operating revenues. 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No authoritative reference available. false 15 Other income 2 us-gaap_OtherNonoperatingIncome us-gaap true credit duration No definition available. false false false false false false false false false false true negated false 1 false true false false -878000 -878 false false false 2 false true false false -738000 -738 false false false 3 false true false false -2550000 -2550 false false false 4 false true false false -2125000 -2125 false false false xbrli:monetaryItemType monetary The aggregate amount of other income amounts resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) profits on securities (net of losses), and (d) miscellaneous other income items. 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If the entity does not present consolidated financial statements, the amount of profit or loss for the period, net of income taxes. 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