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Reportable Segments (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 30, 2017
Segment Reporting Information [Line Items] |  |  |  |
Net interest revenue from external sources | $ 240,883 | $ 218,452 | $ 699,181 | $ 624,838
Net interest revenue (expense) from internal sources | 0 | 0 | 0 | 0
Net interest revenue | 240,883 | 218,452 | 699,181 | 624,838
Provision for credit losses | 4,000 | 0 | (1,000) | 0
Net interest revenue after provision for credit losses | 236,883 | 218,452 | 700,181 | 624,838
Other operating revenue | 167,941 | 175,710 | 480,329 | 528,258
Other operating expense | 252,617 | 265,934 | 743,523 | 761,530
Net direct contribution | 152,207 | 128,228 | 436,987 | 391,566
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 | 152,207 | 128,228 | 436,987 | 391,566
Federal and state income taxes | 34,662 | 42,438 | 98,940 | 128,246
Net income | 117,545 | 85,790 | 338,047 | 263,320
Net income attributable to non-controlling interests | 289 | 141 | 857 | 1,168
Net income attributable to BOK Financial Corp. shareholders | 117,256 | 85,649 | 337,190 | 262,152
Average assets | 33,695,817 | 33,008,170 | 33,775,495 | 32,777,438
Operating Segments [Member] | Commercial [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net interest revenue from external sources | 187,417 | 160,572 | 529,958 | 462,325
Net interest revenue (expense) from internal sources | (42,270) | (25,460) | (107,715) | (65,291)
Net interest revenue | 145,147 | 135,112 | 422,243 | 397,034
Provision for credit losses | 8,047 | 3,217 | 18,781 | 2,982
Net interest revenue after provision for credit losses | 137,100 | 131,895 | 403,462 | 394,052
Other operating revenue | 40,522 | 54,670 | 123,244 | 157,868
Other operating expense | 49,136 | 57,345 | 143,085 | 169,761
Net direct contribution | 128,486 | 129,220 | 383,621 | 382,159
Gain (loss) on financial instruments, net | (3) | 4 | 13 | 46
Change in fair value of mortgage servicing rights | 0 | 0 | 0 | 0
Gain (loss) on repossessed assets, net | (1,869) | (4,126) | (6,102) | (2,728)
Corporate expense allocations | 11,027 | 8,733 | 34,802 | 26,407
Net income before taxes | 115,587 | 116,365 | 342,730 | 353,070
Federal and state income taxes | 30,623 | 47,755 | 90,943 | 144,704
Net income | 84,964 | 68,610 | 251,787 | 208,366
Net income attributable to non-controlling interests | 0 | 0 | 0 | 0
Net income attributable to BOK Financial Corp. shareholders | 84,964 | 68,610 | 251,787 | 208,366
Average assets | 18,499,979 | 17,780,494 | 18,124,571 | 17,738,224
Operating Segments [Member] | Consumer [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net interest revenue from external sources | 21,075 | 21,965 | 64,574 | 61,313
Net interest revenue (expense) from internal sources | 19,039 | 13,981 | 51,811 | 39,845
Net interest revenue | 40,114 | 35,946 | 116,385 | 101,158
Provision for credit losses | 1,451 | 1,316 | 3,890 | 3,515
Net interest revenue after provision for credit losses | 38,663 | 34,630 | 112,495 | 97,643
Other operating revenue | 44,023 | 44,968 | 135,292 | 140,847
Other operating expense | 53,187 | 56,147 | 158,947 | 164,138
Net direct contribution | 29,499 | 23,451 | 88,840 | 74,352
Gain (loss) on financial instruments, net | (7,228) | 1,686 | (36,901) | 5,242
Change in fair value of mortgage servicing rights | 5,972 | (639) | 28,901 | (5,726)
Gain (loss) on repossessed assets, net | (87) | 292 | (21) | 253
Corporate expense allocations | 15,863 | 16,920 | 47,760 | 50,577
Net income before taxes | 12,293 | 7,870 | 33,059 | 23,544
Federal and state income taxes | 3,131 | 3,061 | 8,421 | 9,159
Net income | 9,162 | 4,809 | 24,638 | 14,385
Net income attributable to non-controlling interests | 0 | 0 | 0 | 0
Net income attributable to BOK Financial Corp. shareholders | 9,162 | 4,809 | 24,638 | 14,385
Average assets | 8,323,542 | 8,683,998 | 8,381,204 | 8,469,201
Operating Segments [Member] | Wealth Management [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net interest revenue from external sources | 23,131 | 11,170 | 57,612 | 33,130
Net interest revenue (expense) from internal sources | 6,267 | 9,604 | 26,431 | 28,784
Net interest revenue | 29,398 | 20,774 | 84,043 | 61,914
Provision for credit losses | (84) | (623) | (236) | (676)
Net interest revenue after provision for credit losses | 29,482 | 21,397 | 84,279 | 62,590
Other operating revenue | 83,357 | 75,707 | 228,766 | 225,434
Other operating expense | 62,255 | 61,792 | 186,549 | 182,816
Net direct contribution | 50,584 | 35,312 | 126,496 | 105,208
Gain (loss) on financial instruments, net | 7 | 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 | 11,126 | 9,819 | 33,223 | 30,438
Net income before taxes | 39,465 | 25,493 | 93,280 | 74,770
Federal and state income taxes | 10,134 | 10,021 | 23,982 | 29,450
Net income | 29,331 | 15,472 | 69,298 | 45,320
Net income attributable to non-controlling interests | 0 | 0 | 0 | 0
Net income attributable to BOK Financial Corp. shareholders | 29,331 | 15,472 | 69,298 | 45,320
Average assets | 8,498,363 | 6,992,021 | 8,364,712 | 6,971,369
Funds Management and Other [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net interest revenue from external sources | 9,260 | 24,745 | 47,037 | 68,070
Net interest revenue (expense) from internal sources | 16,964 | 1,875 | 29,473 | (3,338)
Net interest revenue | 26,224 | 26,620 | 76,510 | 64,732
Provision for credit losses | (5,414) | (3,910) | (23,435) | (5,821)
Net interest revenue after provision for credit losses | 31,638 | 30,530 | 99,945 | 70,553
Other operating revenue | 39 | 365 | (6,973) | 4,109
Other operating expense | 88,039 | 90,650 | 254,942 | 244,815
Net direct contribution | (56,362) | (59,755) | (161,970) | (170,153)
Gain (loss) on financial instruments, net | 7,224 | (1,690) | 36,881 | (5,288)
Change in fair value of mortgage servicing rights | (5,972) | 639 | (28,901) | 5,726
Gain (loss) on repossessed assets, net | 1,956 | 3,834 | 6,123 | 2,475
Corporate expense allocations | (38,016) | (35,472) | (115,785) | (107,422)
Net income before taxes | (15,138) | (21,500) | (32,082) | (59,818)
Federal and state income taxes | (9,226) | (18,399) | (24,406) | (55,067)
Net income | (5,912) | (3,101) | (7,676) | (4,751)
Net income attributable to non-controlling interests | 289 | 141 | 857 | 1,168
Net income attributable to BOK Financial Corp. shareholders | (6,201) | (3,242) | (8,533) | (5,919)
Average assets | $ (1,626,067) | $ (448,343) | $ (1,094,992) | $ (401,356)

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