Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953682-111524

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+ References

No definition available.

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Amount representing an agreement for an unconditional promise by the maker to pay the entity (holder) a definite sum of money at a future date. Such amount may include accrued interest receivable in accordance with the terms of the note. The note also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. Excludes amounts related to receivables held-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10(3))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Loans (Troubled debt in text) (Details) - USD ($)	3 Months Ended
Loans (Troubled debt in text) (Details) - USD ($)	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Financing Receivable, Recorded Investment [Line Items]
Number of loans for which there was a payment default (loan)	$ 0	$ 0
Gross loans receivable held to maturity	5,363,737,000		$ 5,353,702,000
Doubtful
Financing Receivable, Recorded Investment [Line Items]
Gross loans receivable held to maturity	0
Loss
Financing Receivable, Recorded Investment [Line Items]
Gross loans receivable held to maturity	$ 0