Fair Value Measurements - Change in FV (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Fair Value, Transfers Between Level 1 and Level 2
Transfers of assets from level 1 to level 2	$ 0	$ 0	$ 0	$ 0
Transfers of assets from level 2 to level 1	0	0	0	0
Transfers of liabilities from level 1 to level 2	0	0	0	0
Transfers of liabilities from level 2 to level 1	0	0	0	0
Fair Value Option
Net Gains (Losses)	295,317	131,173	445,803	227,312
Other Noninterest Income	64,113	55,120	93,537	96,942
Loans Held for Sale
Fair Value Option
Net Gains (Losses)	24,499	17,179	58,478	3,855
Total Changes in Fair Value	24,499	17,179	58,478	3,855
MSR
Fair Value Option
Net Gains (Losses)	(8,475)	(10,901)	(19,505)	(16,815)
Total Changes in Fair Value	$ (8,475)	$ (10,901)	$ (19,505)	$ (16,815)

Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings.

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The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes.

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Represents the total of noninterest income derived from certain activities and assets including (for example): (1) venture capital investments; (2) bank owned life insurance; (3) foreign currency transactions; and (4) mortgage servicing rights.

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