XML 64 R54.htm IDEA: XBRL DOCUMENT
v3.20.2

Reportable Segments (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Segment Reporting Information [Line Items] |  |  |  |  |
Net interest revenue from external sources | $ 271,750 | $ 279,096 | $ 811,214 | $ 842,630 |
Net interest revenue (expense) from internal sources | 0 | 0 | 0 | 0 |
Net interest revenue | 271,750 | 279,096 | 811,214 | 842,630 |
Provision for credit losses | 0 | 12,000 | 229,092 | 25,000 |
Net interest revenue after provision for credit losses | 271,750 | 267,096 | 582,122 | 817,630 |
Other operating revenue | 234,159 | 186,450 | 647,171 | 515,785 |
Other operating expense | 301,265 | 279,292 | 865,276 | 843,586 |
Net direct contribution | 204,644 | 174,254 | 364,017 | 489,829 |
Gain (loss) on financial instruments, net | 0 | 0 | 0 | 0 |
Change in fair value of mortgage servicing rights | 0 | 0 | 0 | 0 |
Gain (loss) on repossessed assets, net | 0 | 0 | 0 | 0 |
Corporate expense allocations | 0 | 0 | 0 | 0 |
Net income before taxes | 204,644 | 174,254 | 364,017 | 489,829 |
Federal and state income taxes | 50,552 | 32,396 | 83,655 | 99,926 |
Net income | 154,092 | 141,858 | 280,362 | 389,903 |
Net income (loss) attributable to non-controlling interests | 58 | (373) | (444) | (503) |
Net income attributable to BOK Financial Corp. shareholders | 154,034 | 142,231 | 280,806 | 390,406 |
Average assets | 48,933,767 | 43,580,348 | 48,140,046 | 41,380,249 |
Operating Segments [Member] | Commercial [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net interest revenue from external sources | 173,248 | 243,944 | 549,464 | 699,239 |
Net interest revenue (expense) from internal sources | (23,302) | (64,984) | (103,002) | (185,235) |
Net interest revenue | 149,946 | 178,960 | 446,462 | 514,004 |
Provision for credit losses | 22,599 | 9,505 | 53,241 | 27,574 |
Net interest revenue after provision for credit losses | 127,347 | 169,455 | 393,221 | 486,430 |
Other operating revenue | 52,021 | 48,832 | 138,139 | 128,055 |
Other operating expense | 66,846 | 69,127 | 190,531 | 183,169 |
Net direct contribution | 112,522 | 149,160 | 340,829 | 431,316 |
Gain (loss) on financial instruments, net | 38 | 28 | 135 | 67 |
Change in fair value of mortgage servicing rights | 0 | 0 | 0 | 0 |
Gain (loss) on repossessed assets, net | (4,332) | 802 | (4,132) | 455 |
Corporate expense allocations | 5,172 | 11,772 | 19,514 | 31,880 |
Net income before taxes | 103,056 | 138,218 | 317,318 | 399,958 |
Federal and state income taxes | 27,959 | 37,232 | 86,254 | 107,171 |
Net income | 75,097 | 100,986 | 231,064 | 292,787 |
Net income (loss) attributable to non-controlling interests | 0 | 0 | 0 | 0 |
Net income attributable to BOK Financial Corp. shareholders | 75,097 | 100,986 | 231,064 | 292,787 |
Average assets | 28,000,183 | 23,973,925 | 26,759,150 | 22,288,960 |
Operating Segments [Member] | Consumer [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net interest revenue from external sources | 15,821 | 27,580 | 60,492 | 75,353 |
Net interest revenue (expense) from internal sources | 17,309 | 20,882 | 55,840 | 76,925 |
Net interest revenue | 33,130 | 48,462 | 116,332 | 152,278 |
Provision for credit losses | 79 | 1,841 | 1,870 | 4,654 |
Net interest revenue after provision for credit losses | 33,051 | 46,621 | 114,462 | 147,624 |
Other operating revenue | 67,808 | 51,221 | 190,062 | 142,780 |
Other operating expense | 59,839 | 59,699 | 173,568 | 171,214 |
Net direct contribution | 41,020 | 38,143 | 130,956 | 119,190 |
Gain (loss) on financial instruments, net | 1,540 | 8,339 | 95,660 | 43,416 |
Change in fair value of mortgage servicing rights | 3,441 | (12,593) | (85,800) | (62,814) |
Gain (loss) on repossessed assets, net | 41 | 214 | 81 | 409 |
Corporate expense allocations | 10,812 | 11,776 | 32,111 | 35,369 |
Net income before taxes | 35,230 | 22,327 | 108,786 | 64,832 |
Federal and state income taxes | 8,974 | 5,687 | 27,709 | 16,513 |
Net income | 26,256 | 16,640 | 81,077 | 48,319 |
Net income (loss) attributable to non-controlling interests | 0 | 0 | 0 | 0 |
Net income attributable to BOK Financial Corp. shareholders | 26,256 | 16,640 | 81,077 | 48,319 |
Average assets | 9,898,119 | 9,827,130 | 9,889,690 | 9,142,491 |
Operating Segments [Member] | Wealth Management [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net interest revenue from external sources | 34,098 | 12,343 | 82,823 | 51,054 |
Net interest revenue (expense) from internal sources | (11,113) | 10,723 | (14,054) | 27,213 |
Net interest revenue | 22,985 | 23,066 | 68,769 | 78,267 |
Provision for credit losses | (51) | (42) | (188) | (209) |
Net interest revenue after provision for credit losses | 23,036 | 23,108 | 68,957 | 78,476 |
Other operating revenue | 111,152 | 89,160 | 315,707 | 248,591 |
Other operating expense | 82,868 | 71,619 | 241,627 | 202,579 |
Net direct contribution | 51,320 | 40,649 | 143,037 | 124,488 |
Gain (loss) on financial instruments, net | 0 | 0 | 7 | 0 |
Change in fair value of mortgage servicing rights | 0 | 0 | 0 | 0 |
Gain (loss) on repossessed assets, net | 0 | 0 | 0 | 0 |
Corporate expense allocations | 9,397 | 9,416 | 25,866 | 26,943 |
Net income before taxes | 41,923 | 31,233 | 117,178 | 97,545 |
Federal and state income taxes | 10,711 | 8,027 | 29,999 | 25,076 |
Net income | 31,212 | 23,206 | 87,179 | 72,469 |
Net income (loss) attributable to non-controlling interests | 0 | 0 | 0 | 0 |
Net income attributable to BOK Financial Corp. shareholders | 31,212 | 23,206 | 87,179 | 72,469 |
Average assets | 16,206,522 | 10,391,225 | 14,888,623 | 9,860,427 |
Funds Management and Other [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net interest revenue from external sources | 48,583 | (4,771) | 118,435 | 16,984 | [1]
Net interest revenue (expense) from internal sources | 17,106 | 33,379 | 61,216 | 81,097 | [1]
Net interest revenue | 65,689 | 28,608 | 179,651 | 98,081 | [1]
Provision for credit losses | (22,627) | 696 | 174,169 | (7,019) | [1]
Net interest revenue after provision for credit losses | 88,316 | 27,912 | 5,482 | 105,100 | [1]
Other operating revenue | 3,178 | (2,763) | 3,263 | (3,641) | [1]
Other operating expense | 91,712 | 78,847 | 259,550 | 286,624 | [1]
Net direct contribution | (218) | (53,698) | (250,805) | (185,165) | [1]
Gain (loss) on financial instruments, net | (1,578) | (8,367) | (95,802) | (43,483) | [1]
Change in fair value of mortgage servicing rights | (3,441) | 12,593 | 85,800 | 62,814 | [1]
Gain (loss) on repossessed assets, net | 4,291 | (1,016) | 4,051 | (864) | [1]
Corporate expense allocations | (25,381) | (32,964) | (77,491) | (94,192) | [1]
Net income before taxes | 24,435 | (17,524) | (179,265) | (72,506) | [1]
Federal and state income taxes | 2,908 | (18,550) | (60,307) | (48,834) | [1]
Net income | 21,527 | 1,026 | (118,958) | (23,672) | [1]
Net income (loss) attributable to non-controlling interests | 58 | (373) | (444) | (503) | [1]
Net income attributable to BOK Financial Corp. shareholders | 21,469 | 1,399 | (118,514) | (23,169) | [1]
Average assets | $ (5,171,057) | $ (611,932) | $ (3,397,417) | $ 88,371 | [1]
[1] | CoBiz operations were included in Funds Management and Other for the first quarter of 2019.

X
- Definition Amount of average assets attributed to the reportable segment for the reporting period. + References No definition available. + Details
Name: | bokf_AverageAssetsForReportingPeriod
Namespace Prefix: | bokf_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Represent allocation of corporate expenses to segments + References No definition available. + Details
Name: | bokf_CorporateExpenseAllocations
Namespace Prefix: | bokf_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Represents gain (loss) on financial instruments, net, used for segment reporting purposes on a summary basis. Includes those gains and losses from derivative contracts, fair value option securities and available for sale securities. Also includes in other-than-temporary impairment losses recognized in earnings. + References No definition available. + Details
Name: | bokf_GainLossonFinancialInstrumentsNet
Namespace Prefix: | bokf_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of interest revenue earned or paid on funds loaned to or borrowed from the funds management unit net of interest expense (cost of borrowed funds accounted for as interest) from internal sources. + References No definition available. + Details
Name: | bokf_NIRexpensefrominternalsources
Namespace Prefix: | bokf_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Represents net direct contribution of segments prior to corporate expense allocations. + References No definition available. + Details
Name: | bokf_Netdirectcontribution
Namespace Prefix: | bokf_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of interest revenue, primarily from loans and securities net of interest expense (cost of borrowed funds accounted for as interest) from external sources. + References No definition available. + Details
Name: | bokf_NirExpenseFromExternalSources
Namespace Prefix: | bokf_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Represents the change in the fair value of mortgage servicing rights used for segment reporting purposes. + References No definition available. + Details
Name: | bokf_SegmentReportingChangeinFairValueofMortgageServicingRights
Namespace Prefix: | bokf_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1B -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669625-108580 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(21)) -URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(25)) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 55 -Paragraph 4K -URI http://asc.fasb.org/extlink&oid=120409616&loc=SL4591552-111686 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1A -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669619-108580 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 21 -URI http://asc.fasb.org/extlink&oid=108774443&loc=SL4613674-111683 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(23)) -URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227 Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=108774443&loc=SL4569643-111683 + Details
Name: | us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of gain (loss) from the difference between the sale price or salvage price and the book value of an asset that was sold or retired, and gain (loss) from the write down of assets from their carrying value to fair value. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 + Details
Name: | us-gaap_GainLossOnSalesOfAssetsAndAssetImpairmentCharges
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 32 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 32 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 30 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8906-108599 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 31 -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8924-108599 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)(1)(i)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599 + Details
Name: | us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 6.I.7) -URI http://asc.fasb.org/extlink&oid=116825942&loc=d3e330036-122817 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32672-109319 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(h)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22663-107794 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 20 -Section 45 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=120385591&loc=d3e38679-109324 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(9)) -URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22658-107794 + Details
Name: | us-gaap_IncomeTaxExpenseBenefit
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of interest income or expense, including any amortization and accretion (as applicable) of discounts and premiums, including consideration of the provisions for loan, lease, credit, and other related losses. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.12) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 + Details
Name: | us-gaap_InterestIncomeExpenseAfterProvisionForLoanLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The net amount of operating interest income (expense). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.10) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 + Details
Name: | us-gaap_InterestIncomeExpenseNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669619-108580 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 31 -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8924-108599 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 11 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22694-107794 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(22)) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 11 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22694-107794 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 32 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721683-107760 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22595-107794 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1B -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669625-108580 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599 Reference 11: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(18)) -URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 Reference 12: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(20)) -URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227 Reference 13: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 Reference 14: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22499-107794 Reference 15: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22663-107794 Reference 16: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 28 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14064-108612 Reference 17: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 30 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8906-108599 Reference 18: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22583-107794 Reference 19: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(g)(1)(ii)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690 Reference 20: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 60B -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121326447&loc=SL5780133-109256 Reference 21: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571 Reference 22: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 32 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599 Reference 23: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22658-107794 + Details
Name: | us-gaap_NetIncomeLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Total aggregate amount of all noninterest expense. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.14) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 + Details
Name: | us-gaap_NoninterestExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The total amount of noninterest income which may be derived from: (1) fees and commissions; (2) premiums earned; (3) insurance policy charges; (4) the sale or disposal of assets; and (5) other sources not otherwise specified. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.13) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 + Details
Name: | us-gaap_NoninterestIncome
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(g)(1)(ii)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669619-108580 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721683-107760 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22499-107794 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 28 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14064-108612 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=109239629&loc=SL4573702-111684 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 235 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-05(b)(2)) -URI http://asc.fasb.org/extlink&oid=120399901&loc=d3e537907-122884 Reference 8: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 31 -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8924-108599 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 1B -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669625-108580 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22663-107794 Reference 11: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599 Reference 12: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 32 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599 Reference 13: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=109239629&loc=SL4573702-111684 Reference 14: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 55 -Paragraph 4J -URI http://asc.fasb.org/extlink&oid=120409616&loc=SL4591551-111686 Reference 15: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 30 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8906-108599 Reference 16: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3000-108585 Reference 17: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 19 -URI http://asc.fasb.org/extlink&oid=108774443&loc=SL4569616-111683 Reference 18: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571 Reference 19: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 32 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599 Reference 20: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 55 -Paragraph 4K -URI http://asc.fasb.org/extlink&oid=120409616&loc=SL4591552-111686 Reference 21: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22658-107794 + Details
Name: | us-gaap_ProfitLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.11) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 + Details
Name: | us-gaap_ProvisionForLoanLeaseAndOtherLosses
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_SegmentReportingRevenueReconcilingItemLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | srt_ConsolidationItemsAxis=us-gaap_OperatingSegmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=bokf_CommercialMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=bokf_ConsumerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=bokf_WealthManagementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ConsolidationItemsAxis=us-gaap_CorporateNonSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |