Derivative Financial Instruments - Schedule of Income Statement Impact (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Derivative settlements, net	$ 7,298	$ 22,324	$ 39,306	$ 51,018
Other Income
Derivative Instruments, Gain (Loss) [Line Items]
Derivative settlements, net	7,298	22,324	39,306	51,018
Change in fair value	(5,630)	(5,226)	(73,265)	49,909
Derivative market value adjustments and derivative settlements, net - income (expense)	1,668	17,098	(33,959)	100,927
1:3 basis swaps \| Other Income
Derivative Instruments, Gain (Loss) [Line Items]
Derivative settlements, net	234	3,361	3,375	4,676
Change in fair value	6,636	1,283	4,427	12,058
Interest rate swaps - floor income hedges \| Other Income
Derivative Instruments, Gain (Loss) [Line Items]
Derivative settlements, net	7,064	19,087	35,931	46,752
Change in fair value	(12,094)	(7,427)	(75,657)	34,008
Interest rate swap options - floor income hedges \| Other Income
Derivative Instruments, Gain (Loss) [Line Items]
Change in fair value	(1)	(31)	(1,465)	437
Interest rate caps \| Other Income
Derivative Instruments, Gain (Loss) [Line Items]
Change in fair value	(171)	119	(570)	567
Interest rate swaps - hybrid debt hedges \| Other Income
Derivative Instruments, Gain (Loss) [Line Items]
Derivative settlements, net	0	(124)	0	(410)
Change in fair value	$ 0	$ 830	$ 0	$ 2,839

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- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959

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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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Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959

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