Derivatives - Derivatives Associated with Fixed Income Trading Activities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Customer Interest Rate Contracts
Derivative Instruments, Gain (Loss) [Line Items]
Notional	$ 2,697,522	$ 2,271,448
Assets	65,768	18,744
Liabilities	6,858	27,768
Offsetting Upstream Interest Rate Contracts
Derivative Instruments, Gain (Loss) [Line Items]
Notional	2,697,522	2,271,448
Assets	2,583	4,014
Liabilities	3,994	9,041
Option Contracts Purchased \| Long
Derivative Instruments, Gain (Loss) [Line Items]
Notional	40,000	20,000
Assets	131	25
Liabilities	0	0
Forwards and Futures Purchased
Derivative Instruments, Gain (Loss) [Line Items]
Notional	9,217,350	4,684,177
Assets	17,029	28,304
Liabilities	3,187	181
Forwards and Futures Sold
Derivative Instruments, Gain (Loss) [Line Items]
Notional	9,403,112	4,967,454
Assets	3,611	522
Liabilities	$ 16,620	$ 30,055

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

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- Definition

Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

+ References

No definition available.

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- Definition

Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

+ References

No definition available.

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