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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

+ References

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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.

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Fair Value of Financial Instruments - Balances and Levels of Assets Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017	Dec. 31, 2016
Financial assets:
Mortgage servicing rights, net	$ 79,890	$ 109,449	$ 76,107	$ 48,464	$ 33,081
Available-for-sale securities, at fair value			543,992
Fair Value, Measurements, Recurring
Financial assets:
Investment securities	609,568
Loans held for sale	323,486		526,185
Mortgage servicing rights, net	79,890		76,107
Derivatives assets	13,662		9,690
Available-for-sale securities, at fair value			543,992
Financial liabilities:
Derivatives liabilities	4,076		1,699
Fair Value, Measurements, Recurring \| U.S. Government Agency Securities
Financial assets:
Investment securities	984
Available-for-sale securities, at fair value			986
Fair Value, Measurements, Recurring \| Mortgage-backed Securities
Financial assets:
Investment securities	467,714
Available-for-sale securities, at fair value			418,781
Fair Value, Measurements, Recurring \| Municipals, Tax Exempt
Financial assets:
Investment securities	130,672
Available-for-sale securities, at fair value			109,251
Fair Value, Measurements, Recurring \| Treasury Securities
Financial assets:
Investment securities	7,131
Available-for-sale securities, at fair value			7,252
Fair Value, Measurements, Recurring \| Equity Securities
Financial assets:
Investment securities	3,067
Available-for-sale securities, at fair value			7,722
Fair Value, Measurements, Recurring \| Significant Other Observable Inputs (Level 2)
Financial assets:
Investment securities	609,568
Loans held for sale	323,486		526,185
Derivatives assets	13,662		9,690
Available-for-sale securities, at fair value			540,388
Financial liabilities:
Derivatives liabilities	4,076		1,699
Fair Value, Measurements, Recurring \| Significant Other Observable Inputs (Level 2) \| U.S. Government Agency Securities
Financial assets:
Investment securities	984
Available-for-sale securities, at fair value			986
Fair Value, Measurements, Recurring \| Significant Other Observable Inputs (Level 2) \| Mortgage-backed Securities
Financial assets:
Investment securities	467,714
Available-for-sale securities, at fair value			418,781
Fair Value, Measurements, Recurring \| Significant Other Observable Inputs (Level 2) \| Municipals, Tax Exempt
Financial assets:
Investment securities	130,672
Available-for-sale securities, at fair value			109,251
Fair Value, Measurements, Recurring \| Significant Other Observable Inputs (Level 2) \| Treasury Securities
Financial assets:
Investment securities	7,131
Available-for-sale securities, at fair value			7,252
Fair Value, Measurements, Recurring \| Significant Other Observable Inputs (Level 2) \| Equity Securities
Financial assets:
Investment securities	3,067
Available-for-sale securities, at fair value			4,118
Fair Value, Measurements, Recurring \| Significant Unobservable Inputs (Level 3)
Financial assets:
Mortgage servicing rights, net	$ 79,890		76,107
Available-for-sale securities, at fair value			3,604
Fair Value, Measurements, Recurring \| Significant Unobservable Inputs (Level 3) \| Equity Securities
Financial assets:
Available-for-sale securities, at fair value			$ 3,604