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v3.20.4

Other Borrowed Funds (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Other Borrowed Funds [Line Items] |  |  |  |
Balance |  | $ 3,821,361 | $ 8,621,328 | $ 7,418,714
Average Balance |  | $ 8,570,959 | $ 10,261,592 | $ 7,298,229
Rate |  | 0.82% | 2.37% | 2.03%
Other borrowed funds, Maturities [Abstract] |  |  |  |
2021 |  | $ 1,884,974 |  |
2022 |  | 1,639,735 |  |
2023 |  | 9,625 |  |
2024 |  | 625 |  |
2025 |  | 10,555 |  |
Thereafter |  | 275,847 |  |
Funds purchased [Member] |  |  |  |
Other Borrowed Funds [Line Items] |  |  |  |
Balance |  | $ 769,365 | $ 3,390,528 | $ 402,450
Rate |  | 0.05% | 1.53% | 2.34%
Average Balance |  | $ 2,045,795 | $ 2,438,376 | $ 419,322
Rate |  | 0.58% | 2.08% | 1.89%
Maximum Outstanding At Any Month End |  | $ 3,311,938 | $ 3,390,528 | $ 949,531
Repurchase agreements [Member] |  |  |  |
Other Borrowed Funds [Line Items] |  |  |  |
Balance |  | $ 893,021 | $ 427,822 | $ 615,961
Rate |  | 0.09% | 0.50% | 0.36%
Average Balance |  | $ 1,589,746 | $ 399,785 | $ 464,582
Rate |  | 0.24% | 0.57% | 0.28%
Maximum Outstanding At Any Month End |  | $ 3,230,097 | $ 427,822 | $ 615,961
Other Borrowings [Member] |  |  |  |
Other Borrowed Funds [Line Items] |  |  |  |
Balance |  | 1,882,970 | 4,527,055 | 6,124,390
Average Balance |  | $ 4,659,453 | $ 7,147,356 | $ 6,236,441
Rate |  | 0.88% | 2.45% | 2.07%
Federal Home Loan Bank advances [Member] |  |  |  |
Other Borrowed Funds [Line Items] |  |  |  |
Balance |  | $ 200,000 | $ 4,500,000 | $ 6,100,000
Rate |  | 0.29% | 1.79% | 2.65%
Average Balance |  | $ 3,393,989 | $ 7,122,466 | $ 6,207,142
Rate |  | 1.00% | 2.44% | 2.06%
Maximum Outstanding At Any Month End |  | $ 7,500,000 | $ 8,000,000 | $ 6,500,000
GNMA repurchase liability [Member] |  |  |  |
Other Borrowed Funds [Line Items] |  |  |  |
Balance |  | $ 19,500 | $ 15,417 | $ 15,552
Rate |  | 4.35% | 4.32% | 4.43%
Average Balance |  | $ 42,771 | $ 13,746 | $ 14,783
Rate |  | 4.18% | 4.47% | 4.47%
Maximum Outstanding At Any Month End |  | $ 126,569 | $ 19,581 | $ 16,529
Federal Reserve Bank Advances |  |  |  |
Other Borrowed Funds [Line Items] |  |  |  |
Balance |  | $ 0 |  |
Rate |  | 0.00% |  |
Average Balance |  | $ 42,464 |  |
Rate |  | 0.26% |  |
Maximum Outstanding At Any Month End |  | $ 0 |  |
Paycheck protection program liquidity facility |  |  |  |
Other Borrowed Funds [Line Items] |  |  |  |
Balance |  | $ 1,635,963 |  |
Rate |  | 0.35% |  |
Average Balance |  | $ 1,152,073 |  |
Rate |  | 0.35% |  |
Maximum Outstanding At Any Month End |  | $ 2,013,414 |  |
Other [Member] |  |  |  |
Other Borrowed Funds [Line Items] |  |  |  |
Balance |  | $ 27,507 | $ 11,638 | $ 8,838
Rate |  | 5.24% | 5.09% | 2.90%
Average Balance |  | $ 28,156 | $ 11,144 | $ 14,516
Rate |  | 5.12% | 5.30% | 2.67%
Maximum Outstanding At Any Month End |  | $ 49,376 | $ 34,676 | $ 20,422
Subordinated debentures [Member] |  |  |  |
Other Borrowed Funds [Line Items] |  |  |  |
Balance | [1] | $ 276,005 | $ 275,923 | $ 275,913
Rate | [1] | 4.72% | 5.15% | 5.34%
Average Balance | [1] | $ 275,965 | $ 276,075 | $ 177,884
Rate | [1] | 5.05% | 5.47% | 5.52%
Maximum Outstanding At Any Month End | [1] | $ 276,005 | $ 275,923 | $ 275,913
Subordinated debentures [Member] | Subordinated debentures, 2016 issuance [Member] |  |  |  |
Other borrowed funds, Other Disclosures [Abstract] |  |  |  |
Amount of debt issuance |  | $ 150,000 |  |
Maturity date |  | Jun. 30, 2056 |  |
Stated interest rate |  | 5.375% |  |
Debt Instrument, Call Date, Earliest |  | Jun. 30, 2021 |  |
Subordinated debentures [Member] | Subordinated debentures-acquired, 2015 Issuance [Member] |  |  |  |
Other borrowed funds, Other Disclosures [Abstract] |  |  |  |
Amount of debt issuance |  | $ 60,000 |  |
Maturity date |  | Jun. 25, 2030 |  |
Interest rate description |  | three-month LIBOR plus 3.17% |  |
Stated interest rate |  | 5.625% |  |
Debt Instrument, Call Date, Earliest |  | Jun. 25, 2025 |  |
Subordinated debentures [Member] | Junior subordinated debentures-acquired, 2003 issuance [Member] |  |  |  |
Other borrowed funds, Other Disclosures [Abstract] |  |  |  |
Amount of debt issuance |  | $ 21,000 |  |
Maturity date |  | Sep. 17, 2033 |  |
Interest rate description |  | three-month LIBOR plus 2.95% |  |
Subordinated debentures [Member] | Junior subordinated debentures-acquired, 2004 issuance [Member] |  |  |  |
Other borrowed funds, Other Disclosures [Abstract] |  |  |  |
Amount of debt issuance |  | $ 31,000 |  |
Maturity date |  | Jul. 23, 2034 |  |
Interest rate description |  | three-month LIBOR plus 2.60% |  |
Subordinated debentures [Member] | Junior subordinated debentures-acquired, 2005 issuance [Member] |  |  |  |
Other borrowed funds, Other Disclosures [Abstract] |  |  |  |
Amount of debt issuance |  | $ 20,000 |  |
Maturity date |  | Sep. 30, 2035 |  |
Interest rate description |  | three-month LIBOR plus 1.45% |  |
U.S. government agency mortgage-backed securities [Member] |  |  |  |
Assets Sold under Agreements to Repurchase [Line Items] |  |  |  |
Amortized Cost |  | $ 893,069 | 431,939 |
Fair Value |  | 910,885 | 435,898 |
Repurchase Liability | [2] | $ 893,021 | $ 427,822 |
Average Rate (in hundredths) |  | 0.09% | 0.50% |
U.S. government agency mortgage-backed securities [Member] | Overnight [Member] |  |  |  |
Assets Sold under Agreements to Repurchase [Line Items] |  |  |  |
Amortized Cost |  | $ 893,069 | $ 431,939 |
Fair Value |  | 910,885 | 435,898 |
Repurchase Liability | [2] | $ 893,021 | $ 427,822 |
Average Rate (in hundredths) |  | 0.09% | 0.50% |
U.S. government agency mortgage-backed securities [Member] | Long-term [Member] |  |  |  |
Assets Sold under Agreements to Repurchase [Line Items] |  |  |  |
Amortized Cost |  | $ 0 | $ 0 |
Fair Value |  | 0 | 0 |
Repurchase Liability | [2] | $ 0 | $ 0 |
Average Rate (in hundredths) |  | 0.00% | 0.00% |
Subsidiaries [Member] | Funds purchased [Member] |  |  |  |
Other borrowed funds, Other Disclosures [Abstract] |  |  |  |
Number of days to maturity, minimum |  | one day |  |
Number of days to maturity, maximum |  | ninety days |  |
Subsidiaries [Member] | Repurchase agreements [Member] |  |  |  |
Other borrowed funds, Other Disclosures [Abstract] |  |  |  |
Number of days to maturity, maximum |  | ninety days |  |
Subsidiaries [Member] | Federal Home Loan Bank advances [Member] |  |  |  |
Other borrowed funds, Other Disclosures [Abstract] |  |  |  |
Federal Home Loan Banks, Letters of credit issued to secure public funds |  | $ 381,000 |  |
Unused credit available pursuant to the FHLB's collateral policies |  | 8,600,000 |  |
Subsidiaries [Member] | BOK Financial Securities, Inc. [Member] | Other [Member] |  |  |  |
Other Borrowed Funds [Line Items] |  |  |  |
Balance |  | $ 0 | $ 0 |
[1] | Parent Company only.
[2] | BOK Financial maintains control over the securities underlying overnight repurchase agreements and generally transfers control over securities underlying longer-term dealer repurchase agreements to the respective counterparty.

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