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Derivatives (Details 2) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2017 USD ($) company | Dec. 31, 2016 USD ($)
Derivative [Line Items] |  |
Derivative liabilities | $ 90,915 | $ 82,323
Derivative assets | 80,466 | 83,780
Derivatives designated as hedging instruments |  |
Derivative [Line Items] |  |
Notional amount | 42,566 | 131,391
Derivative liabilities | 6,648 | 5,976
Derivative assets | 0 | 4,325
Derivatives not designated as hedging instruments |  |
Derivative [Line Items] |  |
Notional amount | 9,942,781 | 8,507,660
Derivative liabilities | 84,267 | 76,347
Derivative assets | 80,466 | 79,455
Interest rate swaps on certificates of deposit | Derivatives designated as hedging instruments |  |
Derivative [Line Items] |  |
Notional amount | 42,566 | 48,365
Derivative liabilities | 6,648 | 5,976
Derivative assets | 0 | 0
Foreign currency forward contracts | Derivatives designated as hedging instruments |  |
Derivative [Line Items] |  |
Notional amount | 0 | 83,026
Derivative liabilities | 0 | 0
Derivative assets | 0 | 4,325
Interest rate swaps and options | Derivatives not designated as hedging instruments |  |
Derivative [Line Items] |  |
Notional amount | 8,742,980 | 7,668,482
Derivative liabilities | 64,212 | 65,131
Derivative assets | 64,822 | 67,578
Notional amount of derivative assets | 4,370,000 | 3,860,000
Notional amount of derivative liabilities | 4,370,000 | 3,810,000
Foreign exchange contracts | Derivatives not designated as hedging instruments |  |
Derivative [Line Items] |  |
Notional amount | 1,131,414 | 767,764
Derivative liabilities | 20,054 | 11,213
Derivative assets | 14,187 | 11,874
RPAs | Derivatives not designated as hedging instruments |  |
Derivative [Line Items] |  |
Notional amount | 68,387 | 71,414
Derivative liabilities | 1 | 3
Derivative assets | $ 2 | $ 3
Weighted average remaining maturity (in years) | 3 years | 3 years 8 months
RPAs | Derivatives not designated as hedging instruments | Long |  |
Derivative [Line Items] |  |
Notional amount | $ 47,800 | $ 48,300
Derivative liabilities | 1 | 3
Interest rate derivative exposure | 92 | 179
RPAs | Derivatives not designated as hedging instruments | Short |  |
Derivative [Line Items] |  |
Notional amount | 20,600 | 23,100
Derivative assets | 2 | 3
Warrants | Derivatives not designated as hedging instruments |  |
Derivative [Line Items] |  |
Notional amount | 0 | 0
Derivative liabilities | 0 | 0
Derivative assets | 1,455 | $ 0
Warrant, Public Companies | Derivatives not designated as hedging instruments |  |
Derivative [Line Items] |  |
Derivative assets | $ 856 |
Number of companies in which warrants are held | company | 4 |
Warrant, Private Companies | Derivatives not designated as hedging instruments |  |
Derivative [Line Items] |  |
Derivative assets | $ 599 |
Number of companies in which warrants are held | company | 32 |

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