Mortgage Servicing Rights (Schedule Of Changes In Carrying Value Of MSR) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Servicing Asset at Fair Value, Amount [Roll Forward]
Balance at beginning of year	$ 33,676	$ 19,103	$ 9,092
Additions from loans sold with servicing retained	33,071	18,341	13,091
Additions from acquisitions	13,806	0	0
Estimate of changes in fair value due to:
Payoffs and paydowns	(5,039)	(2,595)	(2,325)
Changes in valuation inputs or assumptions	(331)	(1,173)	(755)
Fair value at end of year	75,183	33,676	19,103
Unpaid principal balance of mortgage loans serviced for others	$ 6,545,870	$ 2,929,133	$ 1,784,760

This is the sum of principal amount outstanding for both securitized and unsecuritized loans of all types.

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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

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

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

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Servicing Assets At Fair Value, Additions From Loans Sold With Servicing Retained

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