Mortgage Banking Activities, Net (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Mortgage Loans on Real Estate [Line Items]
Mortgage banking activities, net	$ 38,691	$ 10,972	$ 34,994
Investment Fair Value Changes, Net
Mortgage Loans on Real Estate [Line Items]
Changes in fair value of assets	(28,574)	(21,357)	(10,202)
Changes in fair value of risk management derivatives	(9,112)	(9,677)	(7,792)
Mortgage banking activities, net	38,691	10,972	34,994
Residential Mortgage Banking Activities
Mortgage Loans on Real Estate [Line Items]
Other income	2,203	4,040	3,468
Mortgage banking activities, net	40,753	8,268	21,554
Commercial Mortgage Banking Activities
Mortgage Loans on Real Estate [Line Items]
Other income	43	450	541
Mortgage banking activities, net	(2,062)	2,704	13,440
Residential loans at fair value \| Residential Mortgage Banking Activities
Mortgage Loans on Real Estate [Line Items]
Changes in fair value of assets	31,399	53,946	65,202
Sequoia Entities \| Residential Mortgage Banking Activities
Mortgage Loans on Real Estate [Line Items]
Changes in fair value of assets	1,455	(15,261)	(23,839)
Risk management derivatives, net \| Investment Fair Value Changes, Net
Mortgage Loans on Real Estate [Line Items]
Changes in fair value of assets	(9,112)	(9,677)	(7,792)
Risk management derivatives, net \| Residential Mortgage Banking Activities
Mortgage Loans on Real Estate [Line Items]
Changes in fair value of risk management derivatives	5,696	(34,457)	(23,277)
Risk management derivatives, net \| Commercial Mortgage Banking Activities
Mortgage Loans on Real Estate [Line Items]
Changes in fair value of risk management derivatives	(2,538)	(8,011)	(7,890)
Commercial loans, at fair value \| Commercial Mortgage Banking Activities
Mortgage Loans on Real Estate [Line Items]
Changes in fair value of assets	$ 433	$ 10,265	$ 20,789

Increase (Decrease) in Fair Value Adjustments on Assets

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- Definition

The net income attributable to mortgage banking activities. This includes market valuations related to residential and commercial loans, Sequoia IOs, and mortgage banking derivatives, as well as realized gains or losses associated with mortgage loan sales.

+ References

No definition available.

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- Definition

Amount of unrealized gain (loss) related to the fair value of price risk derivatives designated as fair value hedging instruments, as offset by the gain (loss) on the hedged item to the extent that the fair value hedge is determined to be effective.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of fee and financial service revenue classified as other.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(d))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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