Mortgage Loans Serviced for Others, Amount

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- Definition

Number Of Subsidiaries

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- Definition

Servicing Asset, Agreement Term

+ References

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- Definition

Servicing Asset At Amortized Cost, Amortization, Term

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- Definition

Servicing Asset At Fair Value, Disposals, Unpaid Principal Balance

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- Definition

Valuation servicing rights in tranches [Line Items]

+ References

No definition available.

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- Definition

The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy.

+ References

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

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- Definition

Income from mortgage banking activities (fees and commissions) and servicing real estate mortgages, credit cards, and other financial assets held by others net of any related impairment of capitalized service costs. Also includes any premiums received in lieu of regular servicing fees on such loans only as earned over the life of the loans.

+ References

No definition available.

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- Definition

Aggregate amount of servicing assets that are subsequently measured at fair value and servicing assets that are subsequently measured using the amortization method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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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- Definition

Amortized amount of 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
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
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- Definition

Fair value of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

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- Definition

Amount of increase (decrease) in the amortized amount from a decrease (increase) in the valuation allowance applied to the servicing asset for a contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

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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
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122625-111746

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- Definition

Value of input used to measure servicing asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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- Definition

Discount rate used to estimate the fair value of servicing assets and servicing liabilities.

+ 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
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- Definition

Estimated rate of prepayments of principal on servicing assets and servicing liabilities.

+ References

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Goodwill, Core Deposit Intangibles and Other Intangible Assets (Mortgage and Commercial Loans Servicing Narrative) (Details)		3 Months Ended	12 Months Ended
	May 18, 2018 USD ($) subsidiary	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Valuation servicing rights in tranches [Line Items]
Mortgage loans serviced for others			$ 4,100,000,000	$ 3,560,000,000
Custodial escrow balances maintained			23,700,000	17,300,000
Number Of Subsidiaries \| subsidiary	2
Unpaid principal balance		$ 773,900,000
Mortgage servicing rights				6,900,000
Servicing rights, net			31,072,000	25,857,000
Servicing rights, valuation allowance				0
Mortgage Servicing Rights
Valuation servicing rights in tranches [Line Items]
Fair value of mortgage servicing rights			48,680,000	37,081,000
Servicing asset			29,363,000	$ 23,248,000	$ 32,088,000
Prepayment rate (as a percent)				9.73%
Discount rate (as a percent)				9.06%
Fees collected for servicing of mortgage loans			$ 9,900,000	$ 11,600,000	12,100,000
Mortgage Servicing Rights \| Minimum
Valuation servicing rights in tranches [Line Items]
Prepayment rate (as a percent)			7.52%
Discount rate (as a percent)			9.03%
Mortgage Servicing Rights \| Maximum
Valuation servicing rights in tranches [Line Items]
Prepayment rate (as a percent)			10.30%
Discount rate (as a percent)			9.04%
Mortgage Servicing Rights 15-year Tranche
Valuation servicing rights in tranches [Line Items]
Fair value of mortgage servicing rights			$ 6,301,000	4,988,000
Servicing asset			3,880,000	2,858,000
Servicing rights, term	15 years
Servicing rights, valuation allowance			$ 20,000	$ 0
Amortization period			15 years	15 years
Mortgage Servicing Rights 30-year Tranche
Valuation servicing rights in tranches [Line Items]
Fair value of mortgage servicing rights			$ 42,379,000	$ 32,093,000
Servicing asset			25,541,000	20,390,000
Servicing rights, term	30 years
Servicing rights, valuation allowance			$ 38,000	$ 0
Amortization period			30 years	30 years
Commercial Servicing Rights
Valuation servicing rights in tranches [Line Items]
Fair value of mortgage servicing rights			$ 2,134,000	$ 3,221,000
Servicing asset			1,709,000	2,609,000	$ 3,690,000
Fees collected for servicing of mortgage loans			1,600,000	1,700,000
Servicing rights, net			$ 107,400,000	$ 139,900,000
Commercial Servicing Rights \| Minimum
Valuation servicing rights in tranches [Line Items]
Prepayment rate (as a percent)			11.01%	7.27%
Discount rate (as a percent)			13.44%	13.04%
Commercial Servicing Rights \| Maximum
Valuation servicing rights in tranches [Line Items]
Prepayment rate (as a percent)			13.50%	8.88%
Discount rate (as a percent)			16.96%	15.49%
Commercial Servicing Rights less than 20 Years
Valuation servicing rights in tranches [Line Items]
Fair value of mortgage servicing rights			$ 491,000	$ 740,000
Servicing asset			$ 295,000	537,000
Servicing rights, term			20 years
Servicing rights, valuation allowance			$ 0	$ 0
Amortization period			20 years	20 years
Commercial Servicing Rights more than 20 Years
Valuation servicing rights in tranches [Line Items]
Fair value of mortgage servicing rights			$ 1,643,000	$ 2,481,000
Servicing asset			$ 1,414,000	2,084,000
Servicing rights, term			20 years
Servicing rights, valuation allowance			$ 0	$ 12,000
Amortization period			20 years	20 years
Measurement Input, Cap Rate \| Mortgage Servicing Rights \| Minimum
Valuation servicing rights in tranches [Line Items]
Average capitalization rate (percent)			0.0084	0.0091
Measurement Input, Cap Rate \| Mortgage Servicing Rights \| Maximum
Valuation servicing rights in tranches [Line Items]
Average capitalization rate (percent)			0.0125	0.0150
Measurement Input, Cap Rate \| Commercial Servicing Rights \| Minimum
Valuation servicing rights in tranches [Line Items]
Average capitalization rate (percent)			0.0310	0.0310
Measurement Input, Cap Rate \| Commercial Servicing Rights \| Maximum
Valuation servicing rights in tranches [Line Items]
Average capitalization rate (percent)			0.0445	0.0445
First Bank Lubbock Bancshares, Inc. \| Mortgage Servicing Rights
Valuation servicing rights in tranches [Line Items]
Fair value of mortgage servicing rights	$ 7,000,000
Servicing asset	$ 640,700,000