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Fair Value Measurements, Fair Value Of Financial Instruments as Measured On a Recurring Basis (Details) - USD ($) $ in Thousands | Sep. 30, 2018 | Jun. 30, 2018 | Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Dec. 31, 2016
--- | --- | --- | --- | --- | --- | ---
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | $ 1,613,400 |  |  | $ 462,676 |  | $ 614,117 |  |  |
Available for sale securities | 8,072,014 |  |  | 8,321,578 |  | 8,383,199 |  |  |
Fair value option securities | 452,150 |  |  | 755,054 |  | 819,531 |  |  |
Mortgage servicing rights | 284,673 |  | $ 278,719 | 252,867 |  | 245,858 |  | $ 245,239 | $ 247,073
Derviative contracts, net of cash collateral, Assets, Fair value | 349,481 |  |  | 220,502 |  | 352,559 |  |  |
Liabilities: [Abstract] |  |  |  |  |  |  |  |  |
Derivative contracts, net of cash collateral, Liabilities, Fair Value | 252,387 |  |  | 171,963 |  | 336,327 |  |  |
U.S. government agency debentures [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 80,692 |  |  | 21,196 |  | 30,162 |  |  |
U.S. government agency residential mortgage-backed securities [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 1,378,450 |  |  | 392,673 |  | 516,760 |  |  |
Available for sale securities | 5,132,352 |  |  | 5,309,152 |  | 5,326,384 |  |  |
Fair value option securities | 452,150 |  |  | 755,054 |  | 819,531 |  |  |
Municipal and other tax-exempt securities [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 41,345 |  |  | 13,559 |  | 56,148 |  |  |
Available for sale securities | 4,349 |  |  | 27,080 |  | 28,368 |  |  |
Asset-backed securities [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 72,309 |  |  | 23,885 |  | 0 |  |  |
U.S. Treasury [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Available for sale securities | 490 |  |  | 1,000 |  | 999 |  |  |
Privately issued residential mortgage-backed securities [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Available for sale securities | 74,685 |  |  | 93,221 |  | 99,994 |  |  |
Commercial mortgage-backed securities guaranteed by U.S. government agencies [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Available for sale securities | 2,834,691 |  |  | 2,834,961 |  | 2,889,346 |  |  |
Other debt securities [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 40,604 |  |  | 11,363 |  | 11,047 |  |  |
Available for sale securities | 25,447 |  |  | 25,481 |  | 4,153 |  |  |
Perpetual preferred stock [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Available for sale securities |  |  |  | 15,767 |  | 16,245 |  |  |
Equity securities and mutual funds [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Available for sale securities |  |  |  | 14,916 |  | 17,710 |  |  |
Fair Value, Measurements, Recurring [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 1,613,400 |  |  | 462,676 |  | 614,117 |  |  |
Available for sale securities | 8,072,014 |  |  | 8,321,578 |  | 8,383,199 |  |  |
Residential mortgage loans held for sale | 175,866 |  |  | 221,378 |  | 275,643 |  |  |
Mortgage servicing rights | 284,673 | [1] |  | 252,867 | [2] | 245,858 | [3] |  |
Derviative contracts, net of cash collateral, Assets, Fair value | 349,481 | [4] |  | 220,502 | [5] | 352,559 | [6] |  |
Liabilities: [Abstract] |  |  |  |  |  |  |  |  |
Derivative contracts, net of cash collateral, Liabilities, Fair Value | 252,387 | [4] |  | 171,963 | [5] | 336,327 | [6] |  |
Fair Value, Measurements, Recurring [Member] | U.S. government agency debentures [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 80,692 |  |  | 21,196 |  | 30,162 |  |  |
Fair Value, Measurements, Recurring [Member] | U.S. government agency residential mortgage-backed securities [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 1,378,450 |  |  | 392,673 |  | 516,760 |  |  |
Available for sale securities | 5,132,352 |  |  | 5,309,152 |  | 5,326,384 |  |  |
Fair value option securities | 452,150 |  |  | 755,054 |  | 819,531 |  |  |
Fair Value, Measurements, Recurring [Member] | Municipal and other tax-exempt securities [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 41,345 |  |  | 13,559 |  | 56,148 |  |  |
Available for sale securities | 4,349 |  |  | 27,080 |  | 28,368 |  |  |
Fair Value, Measurements, Recurring [Member] | Asset-backed securities [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 72,309 |  |  | 23,885 |  |  |  |  |
Fair Value, Measurements, Recurring [Member] | U.S. Treasury [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Available for sale securities | 490 |  |  | 1,000 |  | 999 |  |  |
Fair Value, Measurements, Recurring [Member] | Privately issued residential mortgage-backed securities [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Available for sale securities | 74,685 |  |  | 93,221 |  | 99,994 |  |  |
Fair Value, Measurements, Recurring [Member] | Commercial mortgage-backed securities guaranteed by U.S. government agencies [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Available for sale securities | 2,834,691 |  |  | 2,834,961 |  | 2,889,346 |  |  |
Fair Value, Measurements, Recurring [Member] | Other debt securities [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 40,604 |  |  | 11,363 |  | 11,047 |  |  |
Available for sale securities | 25,447 |  |  | 25,481 |  | 4,153 |  |  |
Fair Value, Measurements, Recurring [Member] | Perpetual preferred stock [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Available for sale securities |  |  |  | 15,767 |  | 16,245 |  |  |
Fair Value, Measurements, Recurring [Member] | Equity securities and mutual funds [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Available for sale securities |  |  |  | 14,916 |  | 17,710 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 0 |  |  | 0 |  | 0 |  |  |
Available for sale securities | 490 |  |  | 1,000 |  | 3,577 |  |  |
Residential mortgage loans held for sale | 0 |  |  | 0 |  | 0 |  |  |
Mortgage servicing rights | 0 | [1] |  | 0 | [2] | 0 | [3] |  |
Derviative contracts, net of cash collateral, Assets, Fair value | 26,196 | [4] |  | 8,179 | [5] | 8,498 | [6] |  |
Liabilities: [Abstract] |  |  |  |  |  |  |  |  |
Derivative contracts, net of cash collateral, Liabilities, Fair Value | 17,872 | [4] |  | 0 | [5] | 6,903 | [6] |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | U.S. government agency debentures [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 0 |  |  | 0 |  | 0 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | U.S. government agency residential mortgage-backed securities [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 0 |  |  | 0 |  | 0 |  |  |
Available for sale securities | 0 |  |  | 0 |  | 0 |  |  |
Fair value option securities | 0 |  |  | 0 |  | 0 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Municipal and other tax-exempt securities [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 0 |  |  | 0 |  | 0 |  |  |
Available for sale securities | 0 |  |  | 0 |  | 0 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Asset-backed securities [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 0 |  |  | 0 |  |  |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | U.S. Treasury [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Available for sale securities | 490 |  |  | 1,000 |  | 999 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Privately issued residential mortgage-backed securities [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Available for sale securities | 0 |  |  | 0 |  | 0 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Commercial mortgage-backed securities guaranteed by U.S. government agencies [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Available for sale securities | 0 |  |  | 0 |  | 0 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Other debt securities [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 0 |  |  | 0 |  | 0 |  |  |
Available for sale securities | 0 |  |  | 0 |  | 0 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Perpetual preferred stock [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Available for sale securities |  |  |  | 0 |  | 0 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Equity securities and mutual funds [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Available for sale securities |  |  |  | 0 |  | 2,578 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 1,613,400 |  |  | 462,676 |  | 614,117 |  |  |
Available for sale securities | 8,071,052 |  |  | 8,315,304 |  | 8,370,684 |  |  |
Residential mortgage loans held for sale | 159,028 |  |  | 209,079 |  | 263,543 |  |  |
Mortgage servicing rights | 0 | [1] |  | 0 | [2] | 0 | [3] |  |
Derviative contracts, net of cash collateral, Assets, Fair value | 323,285 | [4] |  | 212,323 | [5] | 344,061 | [6] |  |
Liabilities: [Abstract] |  |  |  |  |  |  |  |  |
Derivative contracts, net of cash collateral, Liabilities, Fair Value | 234,515 | [4] |  | 171,963 | [5] | 329,424 | [6] |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. government agency debentures [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 80,692 |  |  | 21,196 |  | 30,162 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. government agency residential mortgage-backed securities [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 1,378,450 |  |  | 392,673 |  | 516,760 |  |  |
Available for sale securities | 5,132,352 |  |  | 5,309,152 |  | 5,326,384 |  |  |
Fair value option securities | 452,150 |  |  | 755,054 |  | 819,531 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Municipal and other tax-exempt securities [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 41,345 |  |  | 13,559 |  | 56,148 |  |  |
Available for sale securities | 4,349 |  |  | 22,278 |  | 23,583 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Asset-backed securities [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 72,309 |  |  | 23,885 |  |  |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. Treasury [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Available for sale securities | 0 |  |  | 0 |  | 0 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Privately issued residential mortgage-backed securities [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Available for sale securities | 74,685 |  |  | 93,221 |  | 99,994 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Commercial mortgage-backed securities guaranteed by U.S. government agencies [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Available for sale securities | 2,834,691 |  |  | 2,834,961 |  | 2,889,346 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Other debt securities [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 40,604 |  |  | 11,363 |  | 11,047 |  |  |
Available for sale securities | 24,975 |  |  | 25,009 |  | 0 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Perpetual preferred stock [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Available for sale securities |  |  |  | 15,767 |  | 16,245 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Equity securities and mutual funds [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Available for sale securities |  |  |  | 14,916 |  | 15,132 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 0 |  |  | 0 |  | 0 |  |  |
Available for sale securities | 472 |  |  | 5,274 |  | 8,938 |  |  |
Residential mortgage loans held for sale | 16,838 |  |  | 12,299 |  | 12,100 |  |  |
Mortgage servicing rights | 284,673 | [1] |  | 252,867 | [2] | 245,858 | [3] |  |
Derviative contracts, net of cash collateral, Assets, Fair value | 0 | [4] |  | 0 | [5] | 0 | [6] |  |
Liabilities: [Abstract] |  |  |  |  |  |  |  |  |
Derivative contracts, net of cash collateral, Liabilities, Fair Value | 0 | [4] |  | 0 | [5] | 0 | [6] |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | U.S. government agency debentures [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 0 |  |  | 0 |  | 0 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | U.S. government agency residential mortgage-backed securities [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 0 |  |  | 0 |  | 0 |  |  |
Available for sale securities | 0 |  |  | 0 |  | 0 |  |  |
Fair value option securities | 0 |  |  | 0 |  | 0 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Municipal and other tax-exempt securities [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 0 |  |  | 0 |  | 0 |  |  |
Available for sale securities |  |  |  | 4,802 |  | 4,785 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Asset-backed securities [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 0 |  |  | 0 |  |  |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | U.S. Treasury [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Available for sale securities | 0 |  |  | 0 |  | 0 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Privately issued residential mortgage-backed securities [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Available for sale securities | 0 |  |  | 0 |  | 0 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Commercial mortgage-backed securities guaranteed by U.S. government agencies [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Available for sale securities | 0 |  |  | 0 |  | 0 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Other debt securities [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Trading securities | 0 |  |  | 0 |  | 0 |  |  |
Available for sale securities | $ 472 |  |  | 472 |  | 4,153 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Perpetual preferred stock [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Available for sale securities |  |  |  | 0 |  | 0 |  |  |
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Equity securities and mutual funds [Member] |  |  |  |  |  |  |  |  |
Assets: [Abstract] |  |  |  |  |  |  |  |  |
Available for sale securities |  |  |  | $ 0 |  | $ 0 |  |  |
[1] | A reconciliation of the beginning and ending fair value of mortgage servicing rights and disclosures of significant assumptions used to determine fair value are presented in Note 6, Mortgage Banking Activities.
[2] | A reconciliation of the beginning and ending fair value of mortgage servicing rights and disclosures of significant assumptions used to determine fair value are presented in Note 6, Mortgage Banking Activities.
[3] | A reconciliation of the beginning and ending fair value of mortgage servicing rights and disclosures of significant assumptions used to determine fair value are presented in Note 6, Mortgage Banking Activities.
[4] | See Note 3 for detail of fair value of derivative contracts by contract type. Derivative contracts in asset positions that were valued based on quoted prices in active markets for identical instruments (Level 1) are primarily exchange-traded interest rate and agricultural derivative contacts, net of cash margin. Derivative contacts in liability positions that were valued using quoted prices in active markets for identical instruments are exchange-traded energy and interest rate derivative contracts, net of cash margin.
[5] | See Note 3 for detail of fair value of derivative contracts by contract type. Derivative contracts based on quoted prices in active markets for identical instruments (Level 1) are exchange-traded interest rate, energy and agricultural derivative contacts. Derivative contracts in liability positions that were valued using quoted prices in active markets for identical instruments (Level 1) are exchange-traded interest rate and energy derivative contracts, fully offset by cash margin.
[6] | See Note 3 for detail of fair value of derivative contracts by contract type. Derivative contracts based on quoted prices in active markets for identical instruments (Level 1) are exchange-traded interest rate, energy and agricultural derivative contacts. Derivative contracts in liability positions that were valued using quoted prices in active markets for identical instruments (Level 1) are exchange-traded interest rate derivative contracts, net cash margin.

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- Definition Fair value option securities represent securities the Company has elected to carry at fair value and separately identified on the balance sheet with changes in fair value recognized in earnings as they occur. Certain residential mortgage-backed securities issued by US government agencies are held as an economic hedge of changes in the fair value of mortgage servicing rights and related derivative contracts. In addition, other securities may be held to manage interest rate risk or for deferred compensation purposes. Securities held for interest rate risk management may be economically hedged by derivative contracts not designated as hedging instruments effectively modify these fixed rate securities into variable rate securities. + References No definition available. + Details
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Namespace Prefix: | bokf_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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- References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26610-111562 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563 + Details
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