Loans - Carrying Value of Loans Pledged (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Loans pledged to secure:
FHLB advances (blanket pledge)	$ 4,443,268	$ 4,587,240
FRB's Discount Window Primary Credit Program	1,166,128	1,099,712
Total	$ 5,609,396	$ 5,686,952

The sum of the carrying amounts, as of the date of the latest financial statement presented, of loans receivable which are owned but transferred to serve as collateral for the payment of related debt obligations, primarily secured borrowings and repurchase agreements, and for which the transferees are not permitted to sell or re-pledge them to an unrelated party.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

+ Details

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Balance Type:	debit
Period Type:	instant

- References

No definition available.

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- Definition

The carrying amount, as of the date of the latest financial statement presented, of loans receivable which are owned but transferred to serve as collateral for the payment of FHLB debt obligations, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

The carrying amount, as of the date of the latest financial statement presented, of loans receivable which are owned but transferred to serve as collateral for the payment of other debt obligations, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

+ References

+ Details

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