Accumulated Other Comprehensive Income - Impact of Reclassifications out of AOCI (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Accumulated Other Comprehensive Income
Interest expense	$ (76,431)	$ (59,082)	$ (213,608)	$ (173,237)
Interest income from investment securities	12,451	19,175	40,045	53,879
Net income	92,799	105,813	318,886	244,930
Amounts Reclassified from AOCI
Accumulated Other Comprehensive Income
Net income	19	(78)	84	(261)
Effective Portion of Cumulative Loss on Cash Flow Hedges \| Interest rate contracts \| Amounts Reclassified from AOCI
Accumulated Other Comprehensive Income
Interest expense	$ 19	$ (78)	(11)	$ (261)
Cumulative Unrealized Gain (Loss) on Available-for-Sale Securities \| Amounts Reclassified from AOCI
Accumulated Other Comprehensive Income
Interest income from investment securities			$ 95

Amount of the cost of borrowed funds accounted for as interest expense.

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Amount of operating interest income, including amortization and accretion of premiums and discounts, on securitized, pass-through debt securities collateralized by real estate mortgage loans.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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