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Reportable Segments (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018
Segment Reporting Information [Line Items] |  |  |  |  |
Net interest revenue from external sources | $ 279,096 | $ 240,883 | $ 842,630 |  | $ 699,181
Net interest revenue (expense) from internal sources | 0 | 0 | 0 |  | 0
Net interest revenue | 279,096 | 240,883 | 842,630 |  | 699,181
Provision for credit losses | 12,000 | 4,000 | 25,000 |  | (1,000)
Net interest revenue after provision for credit losses | 267,096 | 236,883 | 817,630 |  | 700,181
Other operating revenue | 186,450 | 167,941 | 515,785 |  | 480,329
Other operating expense | 279,292 | 252,617 | 843,586 |  | 743,523
Net direct contribution | 174,254 | 152,207 | 489,829 |  | 436,987
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 | 174,254 | 152,207 | 489,829 |  | 436,987
Federal and state income taxes | 32,396 | 34,662 | 99,926 |  | 98,940
Net income | 141,858 | 117,545 | 389,903 |  | 338,047
Net income attributable to non-controlling interests | (373) | 289 | (503) |  | 857
Net income attributable to BOK Financial Corp. shareholders | 142,231 | 117,256 | 390,406 |  | 337,190
Average assets | 43,582,110 | 33,695,817 | 41,380,843 |  | 33,775,495
Operating Segments [Member] | Commercial [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net interest revenue from external sources | 243,944 | 187,417 | 699,239 |  | 529,958
Net interest revenue (expense) from internal sources | (63,797) | (42,270) | (181,829) |  | (107,715)
Net interest revenue | 180,147 | 145,147 | 517,410 |  | 422,243
Provision for credit losses | 9,505 | 8,047 | 27,574 |  | 18,781
Net interest revenue after provision for credit losses | 170,642 | 137,100 | 489,836 |  | 403,462
Other operating revenue | 48,832 | 40,522 | 128,055 |  | 123,245
Other operating expense | 68,685 | 51,039 | 181,809 |  | 148,796
Net direct contribution | 150,789 | 126,583 | 436,082 |  | 377,911
Gain (loss) on financial instruments, net | 28 | (3) | 67 |  | 13
Change in fair value of mortgage servicing rights | 0 | 0 | 0 |  | 0
Gain (loss) on repossessed assets, net | 802 | (1,869) | 455 |  | (6,102)
Corporate expense allocations | 12,613 | 9,124 | 34,146 |  | 29,092
Net income before taxes | 139,006 | 115,587 | 402,458 |  | 342,730
Federal and state income taxes | 37,433 | 30,623 | 107,807 |  | 90,943
Net income | 101,573 | 84,964 | 294,651 |  | 251,787
Net income attributable to non-controlling interests | 0 | 0 | 0 |  | 0
Net income attributable to BOK Financial Corp. shareholders | 101,573 | 84,964 | 294,651 |  | 251,787
Average assets | 23,973,067 | 18,499,979 | 22,288,129 |  | 18,124,571
Operating Segments [Member] | Consumer [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net interest revenue from external sources | 27,580 | 20,005 | 75,353 |  | 63,504
Net interest revenue (expense) from internal sources | 20,882 | 19,039 | 76,925 |  | 51,811
Net interest revenue | 48,462 | 39,044 | 152,278 |  | 115,315
Provision for credit losses | 1,841 | 1,451 | 4,654 |  | 3,890
Net interest revenue after provision for credit losses | 46,621 | 37,593 | 147,624 |  | 111,425
Other operating revenue | 51,221 | 44,024 | 142,780 |  | 135,291
Other operating expense | 59,699 | 58,482 | 171,214 |  | 174,728
Net direct contribution | 38,143 | 23,135 | 119,190 |  | 71,988
Gain (loss) on financial instruments, net | 8,339 | (7,229) | 43,416 |  | (36,901)
Change in fair value of mortgage servicing rights | (12,593) | 5,972 | (62,814) |  | 28,901
Gain (loss) on repossessed assets, net | 214 | (87) | 409 |  | (21)
Corporate expense allocations | 11,776 | 11,037 | 35,369 |  | 33,283
Net income before taxes | 22,327 | 10,754 | 64,832 |  | 30,684
Federal and state income taxes | 5,687 | 2,739 | 16,513 |  | 7,816
Net income | 16,640 | 8,015 | 48,319 |  | 22,868
Net income attributable to non-controlling interests | 0 | 0 | 0 |  | 0
Net income attributable to BOK Financial Corp. shareholders | 16,640 | 8,015 | 48,319 |  | 22,868
Average assets | 9,827,130 | 8,323,543 | 9,142,491 |  | 8,381,205
Operating Segments [Member] | Wealth Management [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net interest revenue from external sources | 12,343 | 22,509 | 51,054 |  | 56,990
Net interest revenue (expense) from internal sources | 10,723 | 6,267 | 27,213 |  | 26,431
Net interest revenue | 23,066 | 28,776 | 78,267 |  | 83,421
Provision for credit losses | (42) | (84) | (209) |  | (238)
Net interest revenue after provision for credit losses | 23,108 | 28,860 | 78,476 |  | 83,659
Other operating revenue | 89,160 | 83,357 | 248,591 |  | 228,766
Other operating expense | 71,619 | 62,256 | 202,579 |  | 188,691
Net direct contribution | 40,649 | 49,961 | 124,488 |  | 123,734
Gain (loss) on financial instruments, net | 0 | 7 | 0 |  | 7
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 | 9,416 | 11,127 | 26,943 |  | 31,084
Net income before taxes | 31,233 | 38,841 | 97,545 |  | 92,657
Federal and state income taxes | 8,027 | 9,975 | 25,076 |  | 23,824
Net income | 23,206 | 28,866 | 72,469 |  | 68,833
Net income attributable to non-controlling interests | 0 | 0 | 0 |  | 0
Net income attributable to BOK Financial Corp. shareholders | 23,206 | 28,866 | 72,469 |  | 68,833
Average assets | 10,392,988 | 8,498,363 | 9,861,021 |  | 8,364,712
Funds Management and Other [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net interest revenue from external sources | (4,771) | 10,952 | 16,984 | [1] | 48,729
Net interest revenue (expense) from internal sources | 32,192 | 16,964 | 77,691 | [1] | 29,473
Net interest revenue | 27,421 | 27,916 | 94,675 | [1] | 78,202
Provision for credit losses | 696 | (5,414) | (7,019) | [1] | (23,433)
Net interest revenue after provision for credit losses | 26,725 | 33,330 | 101,694 | [1] | 101,635
Other operating revenue | (2,763) | 38 | (3,641) | [1] | (6,973)
Other operating expense | 79,289 | 80,840 | 287,984 | [1] | 231,308
Net direct contribution | (55,327) | (47,472) | (189,931) | [1] | (136,646)
Gain (loss) on financial instruments, net | (8,367) | 7,225 | (43,483) | [1] | 36,881
Change in fair value of mortgage servicing rights | 12,593 | (5,972) | 62,814 | [1] | (28,901)
Gain (loss) on repossessed assets, net | (1,016) | 1,956 | (864) | [1] | 6,123
Corporate expense allocations | (33,805) | (31,288) | (96,458) | [1] | (93,459)
Net income before taxes | (18,312) | (12,975) | (75,006) | [1] | (29,084)
Federal and state income taxes | (18,751) | (8,675) | (49,470) | [1] | (23,643)
Net income | 439 | (4,300) | (25,536) | [1] | (5,441)
Net income attributable to non-controlling interests | (373) | 289 | (503) | [1] | 857
Net income attributable to BOK Financial Corp. shareholders | 812 | (4,589) | (25,033) | [1] | (6,298)
Average assets | $ (611,075) | $ (1,626,068) | $ 89,202 | [1] | $ (1,094,993)
[1] | CoBiz operations are included in Funds Management and Other for the first quarter of 2019 and subsequently allocated to the respective segments in the second quarter of 2019.

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