Other Investments - Mortgage Servicing Rights (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Servicing Asset at Fair Value, Amount [Roll Forward]
Balance at beginning of period			$ 286,778
Additions			868	$ 0
Changes in fair value due to:
Balance at End of Period	$ 236,632		236,632
Mortgage servicing rights
Servicing Asset at Fair Value, Amount [Roll Forward]
Balance at beginning of period	55,284	$ 66,496	60,281	63,598
Additions	764	0	868	0
Sales	0	(1,077)	0	(1,077)
Changes in fair value due to:
Changes in assumptions	(6,555)	943	(10,141)	5,289
Other changes	(2,097)	(1,688)	(3,612)	(3,136)
Balance at End of Period	47,396	64,674	47,396	64,674
Servicing income	3,850	3,802	7,460	7,597
Cost of sub-servicer	(268)	(338)	(771)	(930)
Net servicing fee income	3,582	3,464	6,689	6,667
Market valuation changes of MSRs	(8,652)	(745)	(13,753)	2,147
Market valuation changes of associated derivatives	6,517	(1,122)	8,768	(6,261)
MSR reversal of provision for repurchases	207	277	207	277
MSR Income, Net	$ 1,654	$ 1,874	$ 1,911	$ 2,830

Market Valuation Changes In Associated Derivatives

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- Definition

Mortgage Servicing Expense

+ References

No definition available.

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- Definition

Includes income from mortgage banking servicing real estate mortgages, net of subservicing costs, and market valuation changes of MSRs held at fair value.

+ References

No definition available.

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- Definition

Provision For Mortgage Servicing Rights Repurchases

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No definition available.

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- Definition

Total net change in market value related to mortgage servicing rights.

+ References

No definition available.

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- Definition

Amount of increase (decrease) in fair value from changes in the assumptions or model used to calculate the fair value of a contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

No definition available.

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- Definition

All amounts that, per contract, are due to the servicer in exchange for servicing the financial asset and would no longer be received by a servicer if the beneficial owners of the serviced assets (or their trustees or agents) were to exercise their actual or potential authority under the contract to shift the servicing to another servicer. Depending on the servicing contract, those fees may include some or all of the difference between the interest rate collected on the asset being serviced and the rate to be paid to the beneficial owners of the asset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122596-111746

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- Definition

Amount of contractually specified servicing fee, late fee, and ancillary fee recognized as income for servicing asset and servicing liability.

+ References

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- Definition

The value of new servicing assets, subsequently measured at fair value, acquired or created during the current period through purchases or from transfers of financial assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
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- Definition

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Decrease in servicing assets subsequently measured at fair value resulting from conveyance of servicing rights to unrelated parties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of increase (decrease) from changes in fair value classified as other for a contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 50
-Section 50
-Paragraph 3
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