1.0.0.3 true CONSOLIDATED STATEMENT OF CHANGES IN PARTNERS' EQUITY (USD $) In Thousands, except Share data false 1 $ false false u000 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 u001 Standard http://www.xbrl.org/2003/instance shares xbrli 0 u002 Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 false 2 $ false false u000 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 u001 Standard http://www.xbrl.org/2003/instance shares xbrli 0 u002 Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 false 3 $ false false u000 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 u001 Standard http://www.xbrl.org/2003/instance shares xbrli 0 u002 Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 false 4 $ false false u000 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 2 Partners' capital, beginning balance 2 us-gaap_PartnersCapital us-gaap true credit instant monetary No definition available. false false false false false false true false false 1 true true 2915966000 2915966 false false 2 true true 2200980000 2200980 false false 3 true true 2194268000 2194268 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 4 Net income 2 us-gaap_ProfitLoss us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 434704000 434704 false false 2 false true 626057000 626057 false false 3 false true 408163000 408163 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 5 Other comprehensive loss (Note G) 2 us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecrease us-gaap true na duration monetary No definition available. false false false false false false false false false 1 false true -86442000 -86442 false false 2 false true 82546000 82546 false false 3 false true -16555000 -16555 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 6 Issuance of common units, value (Note J) 2 us-gaap_PartnersCapitalAccountSaleOfUnits us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 241642000 241642 false false 2 false true 450198000 450198 false false 3 false false 0 0 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 8 Contribution from general partner (Note J) 2 oks_PartnersCapitalAccountContributionFromGeneralPartner oks false credit duration monetary Total contribution made by general partner during the reporting period. false false false false false false false false false 1 false true 5130000 5130 false false 2 false true 9508000 9508 false false 3 false false 0 0 false false 4 false false 0 0 false false Total contribution made by general partner during the reporting period. No authoritative reference available. false 9 Other 2 us-gaap_PartnersCapitalOther us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false true -30000 -30 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 10 Distributions paid (Note J) 2 us-gaap_PartnersCapitalAccountDistributions us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true -500939000 -500939 false false 2 false true -453323000 -453323 false false 3 false true -384866000 -384866 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 11 Partners' capital, ending balance 2 us-gaap_PartnersCapital us-gaap true credit instant monetary No definition available. false false false false false false false true false 1 false true 3010061000 3010061 false false 2 false true 2915966000 2915966 false false 3 false true 2200980000 2200980 false false 4 false true 2194268000 2194268 false false No definition available. No authoritative reference available. false 13 General Partners [Member] 0 na true na na na No definition available. false true false false false false false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false false 0 0 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 14 Partners' capital, beginning balance 2 us-gaap_PartnersCapital us-gaap true credit instant monetary No definition available. false false false false false false true false false 1 false true 77546000 77546 false false 2 false true 58415000 58415 false false 3 false true 54373000 54373 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 16 Net income 2 us-gaap_ProfitLoss us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 96421000 96421 false false 2 false true 88554000 88554 false false 3 false true 58781000 58781 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 17 Other comprehensive loss (Note G) 2 us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecrease us-gaap true na duration monetary No definition available. false false false false false false false false false 1 false true 0 0 false false 2 false true 0 0 false false 3 false true 0 0 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 18 Issuance of common units, value (Note J) 2 us-gaap_PartnersCapitalAccountSaleOfUnits us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 0 0 false false 2 false true 0 0 false false 3 false false 0 0 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 20 Contribution from general partner (Note J) 2 oks_PartnersCapitalAccountContributionFromGeneralPartner oks false credit duration monetary Total contribution made by general partner during the reporting period. false false false false false false false false false 1 false true 5130000 5130 false false 2 false true 9508000 9508 false false 3 false false 0 0 false false 4 false false 0 0 false false Total contribution made by general partner during the reporting period. No authoritative reference available. false 21 Other 2 us-gaap_PartnersCapitalOther us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false true -1000 -1 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 22 Distributions paid (Note J) 2 us-gaap_PartnersCapitalAccountDistributions us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true -94663000 -94663 false false 2 false true -78931000 -78931 false false 3 false true -54738000 -54738 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 23 Partners' capital, ending balance 2 us-gaap_PartnersCapital us-gaap true credit instant monetary No definition available. false false false false false false false true false 1 false true 84434000 84434 false false 2 false true 77546000 77546 false false 3 false true 58415000 58415 false false 4 false true 54373000 54373 false false No definition available. No authoritative reference available. false 25 Common Units [Member] 0 na true na na na No definition available. false true false false false false false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false false 0 0 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 26 Partners' capital, beginning balance 2 us-gaap_PartnersCapital us-gaap true credit instant monetary No definition available. false false false false false false true false false 1 false true 1361058000 1361058 false false 2 false true 814266000 814266 false false 3 false true 803599000 803599 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 27 Partners' capital account, units, beginning balance 2 us-gaap_PartnersCapitalAccountUnits us-gaap true na instant shares No definition available. false false false false false false true false false 1 false true 54426087 54426087.00 false false 2 false true 46397214 46397214.00 false false 3 false true 46397214 46397214.00 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 28 Net income 2 us-gaap_ProfitLoss us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 206633000 206633 false false 2 false true 317226000 317226 false false 3 false true 195329000 195329 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 29 Other comprehensive loss (Note G) 2 us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecrease us-gaap true na duration monetary No definition available. false false false false false false false false false 1 false true 0 0 false false 2 false true 0 0 false false 3 false true 0 0 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 30 Issuance of common units, value (Note J) 2 us-gaap_PartnersCapitalAccountSaleOfUnits us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 241642000 241642 false false 2 false true 450198000 450198 false false 3 false false 0 0 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 31 Issuance of common units, units (Note J) 2 us-gaap_PartnersCapitalAccountUnitsSaleOfUnits us-gaap true na duration shares No definition available. false false false false false false false false false 1 false true 5486690 5486690.00 false false 2 false true 8028873 8028873.00 false false 3 false false 0 0 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 32 Contribution from general partner (Note J) 2 oks_PartnersCapitalAccountContributionFromGeneralPartner oks false credit duration monetary Total contribution made by general partner during the reporting period. false false false false false false false false false 1 false true 0 0 false false 2 false true 0 0 false false 3 false false 0 0 false false 4 false false 0 0 false false Total contribution made by general partner during the reporting period. No authoritative reference available. false 33 Other 2 us-gaap_PartnersCapitalOther us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false true 0 0 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 34 Distributions paid (Note J) 2 us-gaap_PartnersCapitalAccountDistributions us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true -247571000 -247571 false false 2 false true -220632000 -220632 false false 3 false true -184662000 -184662 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 35 Partners' capital, ending balance 2 us-gaap_PartnersCapital us-gaap true credit instant monetary No definition available. false false false false false false false true false 1 false true 1561762000 1561762 false false 2 false true 1361058000 1361058 false false 3 false true 814266000 814266 false false 4 false true 803599000 803599 false false No definition available. No authoritative reference available. false 36 Partners' capital account, units, ending balance 2 us-gaap_PartnersCapitalAccountUnits us-gaap true na instant shares No definition available. false false false false false false false true false 1 false true 59912777 59912777.00 false false 2 false true 54426087 54426087.00 false false 3 false true 46397214 46397214.00 false false 4 false true 46397214 46397214.00 false false No definition available. No authoritative reference available. false 37 Class B Units [Member] 0 na true na na na No definition available. false true false false false false false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false false 0 0 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 38 Partners' capital, beginning balance 2 us-gaap_PartnersCapital us-gaap true credit instant monetary No definition available. false false false false false false true false false 1 false true 1407016000 1407016 false false 2 false true 1340638000 1340638 false false 3 false true 1332276000 1332276 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 39 Partners' capital account, units, beginning balance 2 us-gaap_PartnersCapitalAccountUnits us-gaap true na instant shares No definition available. false false false false false false true false false 1 false true 36494126 36494126.00 false false 2 false true 36494126 36494126.00 false false 3 false true 36494126 36494126.00 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 40 Net income 2 us-gaap_ProfitLoss us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 131302000 131302 false false 2 false true 219836000 219836 false false 3 false true 153637000 153637 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 41 Other comprehensive loss (Note G) 2 us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecrease us-gaap true na duration monetary No definition available. false false false false false false false false false 1 false true 0 0 false false 2 false true 0 0 false false 3 false true 0 0 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 42 Issuance of common units, value (Note J) 2 us-gaap_PartnersCapitalAccountSaleOfUnits us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 0 0 false false 2 false true 0 0 false false 3 false false 0 0 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 43 Issuance of common units, units (Note J) 2 us-gaap_PartnersCapitalAccountUnitsSaleOfUnits us-gaap true na duration shares No definition available. false false false false false false false false false 1 false true 0 0 false false 2 false true 0 0 false false 3 false false 0 0 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 44 Contribution from general partner (Note J) 2 oks_PartnersCapitalAccountContributionFromGeneralPartner oks false credit duration monetary Total contribution made by general partner during the reporting period. false false false false false false false false false 1 false true 0 0 false false 2 false true 0 0 false false 3 false false 0 0 false false 4 false false 0 0 false false Total contribution made by general partner during the reporting period. No authoritative reference available. false 45 Other 2 us-gaap_PartnersCapitalOther us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false true -29000 -29 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 46 Distributions paid (Note J) 2 us-gaap_PartnersCapitalAccountDistributions us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true -158019000 -158019 false false 2 false true -153458000 -153458 false false 3 false true -145246000 -145246 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 47 Partners' capital, ending balance 2 us-gaap_PartnersCapital us-gaap true credit instant monetary No definition available. false false false false false false false true false 1 false true 1380299000 1380299 false false 2 false true 1407016000 1407016 false false 3 false true 1340638000 1340638 false false 4 false true 1332276000 1332276 false false No definition available. No authoritative reference available. false 48 Partners' capital account, units, ending balance 2 us-gaap_PartnersCapitalAccountUnits us-gaap true na instant shares No definition available. false false false false false false false true false 1 false true 36494126 36494126.00 false false 2 false true 36494126 36494126.00 false false 3 false true 36494126 36494126.00 false false 4 false true 36494126 36494126.00 false false No definition available. No authoritative reference available. false 49 Accumulated Other Comprehensive Income (Loss) [Member] 0 na true na na na No definition available. false true false false false false false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false false 0 0 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 50 Partners' capital, beginning balance 2 us-gaap_PartnersCapital us-gaap true credit instant monetary No definition available. false false false false false false true false false 1 false true 64405000 64405 false false 2 false true -18141000 -18141 false false 3 false true -1586000 -1586 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 52 Net income 2 us-gaap_ProfitLoss us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 0 0 false false 2 false true 0 0 false false 3 false true 0 0 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 53 Other comprehensive loss (Note G) 2 us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecrease us-gaap true na duration monetary No definition available. false false false false false false false false false 1 false true -86442000 -86442 false false 2 false true 82546000 82546 false false 3 false true -16555000 -16555 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 54 Issuance of common units, value (Note J) 2 us-gaap_PartnersCapitalAccountSaleOfUnits us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 0 0 false false 2 false true 0 0 false false 3 false false 0 0 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 56 Contribution from general partner (Note J) 2 oks_PartnersCapitalAccountContributionFromGeneralPartner oks false credit duration monetary Total contribution made by general partner during the reporting period. false false false false false false false false false 1 false true 0 0 false false 2 false true 0 0 false false 3 false false 0 0 false false 4 false false 0 0 false false Total contribution made by general partner during the reporting period. No authoritative reference available. false 57 Other 2 us-gaap_PartnersCapitalOther us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false true 0 0 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 58 Distributions paid (Note J) 2 us-gaap_PartnersCapitalAccountDistributions us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 0 0 false false 2 false true 0 0 false false 3 false true 0 0 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 59 Partners' capital, ending balance 2 us-gaap_PartnersCapital us-gaap true credit instant monetary No definition available. false false false false false false false true false 1 false true -22037000 -22037 false false 2 false true 64405000 64405 false false 3 false true -18141000 -18141 false false 4 false true -1586000 -1586 false false No definition available. No authoritative reference available. false 61 Noncontrolling Interests in Consolidated Subsidiaries [Member] 0 na true na na na No definition available. false true false false false false false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false false 0 0 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 62 Partners' capital, beginning balance 2 us-gaap_PartnersCapital us-gaap true credit instant monetary No definition available. false false false false false false true false false 1 false true 5941000 5941 false false 2 false true 5802000 5802 false false 3 false true 5606000 5606 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 64 Net income 2 us-gaap_ProfitLoss us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 348000 348 false false 2 false true 441000 441 false false 3 false true 416000 416 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 65 Other comprehensive loss (Note G) 2 us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecrease us-gaap true na duration monetary No definition available. false false false false false false false false false 1 false true 0 0 false false 2 false true 0 0 false false 3 false true 0 0 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 66 Issuance of common units, value (Note J) 2 us-gaap_PartnersCapitalAccountSaleOfUnits us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 0 0 false false 2 false true 0 0 false false 3 false false 0 0 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 68 Contribution from general partner (Note J) 2 oks_PartnersCapitalAccountContributionFromGeneralPartner oks false credit duration monetary Total contribution made by general partner during the reporting period. false false false false false false false false false 1 false true 0 0 false false 2 false true 0 0 false false 3 false false 0 0 false false 4 false false 0 0 false false Total contribution made by general partner during the reporting period. No authoritative reference available. false 69 Other 2 us-gaap_PartnersCapitalOther us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false true 0 0 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 70 Distributions paid (Note J) 2 us-gaap_PartnersCapitalAccountDistributions us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true -686000 -686 false false 2 false true -302000 -302 false false 3 false true -220000 -220 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 71 Partners' capital, ending balance 2 us-gaap_PartnersCapital us-gaap true credit instant monetary No definition available. false false false false false false false true false 1 true true 5603000 5603 false false 2 true true 5941000 5941 false false 3 true true 5802000 5802 false false 4 true true 5606000 5606 false false No definition available. No authoritative reference available. false false 4 59 false Thousands NoRounding UnKnown false true