Note 5 - Loans and Allowance for Credit Losses - Risk Category of Loans (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Current fiscal year	$ 406,825		$ 406,825		$ 1,269,989
Fiscal year before current	1,092,619		1,092,619		639,745
Two fiscal year before current	481,608		481,608		467,976
Three fiscal year before current	335,474		335,474		217,682
Four fiscal year before current	200,339		200,339		225,463
Five fiscal year before current	504,724		504,724		371,945
Revolving	99,363		99,363		143,563
Revolving converted to term loans	0		0		86
Loans, gross	3,120,952		3,120,952		3,336,449
YTD period charge-offs	2,217	$ 49	2,992	$ 151
YTD period recoveries	11	176	49	238
Net, Current fiscal year	0		0		0
Net, Fiscal year before current	(2,157)		(2,157)		(210)
Net, Two fiscal year before current	(153)		(153)		2
Net, Three fiscal year before current	(561)		(561)		(5)
Net, Four fiscal year before current	0		0		0
Net, Five fiscal year before current	(72)		(72)		215
Net, Revolving	0		0		0
Net, Revolving converted to term loans			0		0
Net			(2,943)		2
Net recoveries (charge-offs), Current fiscal year	0		0		0
Pass [Member]
Current fiscal year	406,522		406,522		1,269,597
Fiscal year before current	1,082,162		1,082,162		633,710
Two fiscal year before current	469,536		469,536		444,480
Three fiscal year before current	317,651		317,651		215,246
Four fiscal year before current	189,618		189,618		211,030
Five fiscal year before current	457,379		457,379		325,621
Revolving	95,468		95,468		132,501
Revolving converted to term loans	0		0		86
Loans, gross	3,018,336		3,018,336		3,232,271
Special Mention [Member]
Current fiscal year	0		0		0
Fiscal year before current	0		0		5,987
Two fiscal year before current	12,036		12,036		9,280
Three fiscal year before current	0		0		0
Four fiscal year before current	7,778		7,778		5,563
Five fiscal year before current	8,766		8,766		17,805
Revolving	2,632		2,632		3,577
Revolving converted to term loans	0		0		0
Loans, gross	31,212		31,212		42,212
Substandard [Member]
Current fiscal year	303		303		392
Fiscal year before current	10,457		10,457		48
Two fiscal year before current	36		36		14,216
Three fiscal year before current	17,823		17,823		2,436
Four fiscal year before current	2,943		2,943		8,870
Five fiscal year before current	38,579		38,579		28,519
Revolving	1,260		1,260		7,485
Revolving converted to term loans	0		0		0
Loans, gross	71,401		71,401		61,966
Doubtful [Member]
Current fiscal year	0		0		0
Fiscal year before current	0		0		0
Two fiscal year before current	0		0		0
Three fiscal year before current	0		0		0
Four fiscal year before current	0		0		0
Five fiscal year before current	0		0		0
Revolving	3		3		0
Revolving converted to term loans	0		0		0
Loans, gross	3		3		0
Construction And Land Development Loans [Member]
Current fiscal year	198,431		198,431		125,216
Fiscal year before current	34,695		34,695		52,262
Two fiscal year before current	22,365		22,365		99,016
Three fiscal year before current	3,925		3,925		201
Four fiscal year before current	195		195		0
Five fiscal year before current	167		167		181
Revolving	0		0		0
Revolving converted to term loans	0		0		0
Loans, gross	259,778		259,778		276,876
YTD period charge-offs, current			(0)		(0)
YTD period charge-offs, one year before			(0)		(0)
YTD period charge-offs, two years before			(0)		(0)
YTD period charge-offs, three years before			(0)		(0)
YTD period charge-offs, four years before			(0)		(0)
YTD period charge-offs, prior			12		(0)
YTD period charge-offs, revolving			(0)		(0)
YTD period charge-offs, converted to term loan			(0)		(0)
YTD period charge-offs			12		(0)
YTD period recoveries, Current fiscal year	0		0		0
YTD period recoveries, Fiscal year before current	0		0		0
YTD period recoveries, Two fiscal year before current	0		0		0
YTD period recoveries, Three fiscal year before current	0		0		0
YTD period recoveries, Four fiscal year before current	0		0		0
YTD period recoveries, Five fiscal year before current	0		0		0
YTD period recoveries, Revolving	0		0		0
YTD period recoveries, Revolving converted to term loans			0		0
YTD period recoveries			0		0
Net, Current fiscal year	0		0		0
Net, Fiscal year before current	0		0		0
Net, Two fiscal year before current	0		0		0
Net, Three fiscal year before current	0		0		0
Net, Four fiscal year before current	0		0		0
Net, Five fiscal year before current	(12)		(12)		0
Net, Revolving	0		0		0
Net, Revolving converted to term loans			0		0
Net			(12)		0
Net recoveries (charge-offs), Current fiscal year	0		0		0
Construction And Land Development Loans [Member] \| Pass [Member]
Current fiscal year	198,431		198,431		125,216
Fiscal year before current	34,695		34,695		52,262
Two fiscal year before current	10,659		10,659		99,016
Three fiscal year before current	3,925		3,925		201
Four fiscal year before current	195		195		0
Five fiscal year before current	39		39		40
Revolving	0		0		0
Revolving converted to term loans	0		0		0
Loans, gross	247,944		247,944		276,735
Construction And Land Development Loans [Member] \| Special Mention [Member]
Current fiscal year	0		0		0
Fiscal year before current	0		0		0
Two fiscal year before current	11,706		11,706		0
Three fiscal year before current	0		0		0
Four fiscal year before current	0		0		0
Five fiscal year before current	0		0		0
Revolving	0		0		0
Revolving converted to term loans	0		0		0
Loans, gross	11,706		11,706		0
Construction And Land Development Loans [Member] \| Substandard [Member]
Current fiscal year	0		0		0
Fiscal year before current	0		0		0
Two fiscal year before current	0		0		0
Three fiscal year before current	0		0		0
Four fiscal year before current	0		0		0
Five fiscal year before current	128		128		141
Revolving	0		0		0
Revolving converted to term loans	0		0		0
Loans, gross	128		128		141
Construction And Land Development Loans [Member] \| Doubtful [Member]
Current fiscal year	0		0		0
Fiscal year before current	0		0		0
Two fiscal year before current	0		0		0
Three fiscal year before current	0		0		0
Four fiscal year before current	0		0		0
Five fiscal year before current	0		0		0
Revolving	0		0		0
Revolving converted to term loans	0		0		0
Loans, gross	0		0		0
Commercial Real Estate Portfolio Segment [Member]
Current fiscal year	56,474		56,474		479,591
Fiscal year before current	438,212		438,212		293,058
Two fiscal year before current	189,451		189,451		212,983
Three fiscal year before current	190,462		190,462		112,771
Four fiscal year before current	107,330		107,330		73,235
Five fiscal year before current	182,281		182,281		140,494
Revolving	0		0		0
Revolving converted to term loans	0		0		0
Loans, gross	1,164,210		1,164,210		1,312,132
YTD period charge-offs, current			(0)		(0)
YTD period charge-offs, one year before			2,078		(0)
YTD period charge-offs, two years before			(0)		(0)
YTD period charge-offs, three years before			459		(0)
YTD period charge-offs, four years before			(0)		(0)
YTD period charge-offs, prior			(0)		(0)
YTD period charge-offs, revolving			(0)		(0)
YTD period charge-offs, converted to term loan			(0)		(0)
YTD period charge-offs	2,150	(0)	2,642	(0)	(0)
YTD period recoveries, Current fiscal year	0		0		0
YTD period recoveries, Fiscal year before current	0		0		0
YTD period recoveries, Two fiscal year before current	0		0		0
YTD period recoveries, Three fiscal year before current	0		0		0
YTD period recoveries, Four fiscal year before current	0		0		0
YTD period recoveries, Five fiscal year before current	0		0		0
YTD period recoveries, Revolving	0		0		0
YTD period recoveries, Revolving converted to term loans			0		0
YTD period recoveries	0	$ 0	0	$ 0	0
Net, Current fiscal year	0		0		0
Net, Fiscal year before current	(2,078)		(2,078)		0
Net, Two fiscal year before current	0		0		0
Net, Three fiscal year before current	(459)		(459)		0
Net, Four fiscal year before current	0		0		0
Net, Five fiscal year before current	0		0		0
Net, Revolving	0		0		0
Net, Revolving converted to term loans			0		0
Net			(2,537)		0
Net recoveries (charge-offs), Current fiscal year	0		0		0
Commercial Real Estate Portfolio Segment [Member] \| Pass [Member]
Current fiscal year	56,171		56,171		479,304
Fiscal year before current	428,412		428,412		293,058
Two fiscal year before current	189,451		189,451		195,051
Three fiscal year before current	178,948		178,948		110,442
Four fiscal year before current	97,249		97,249		73,013
Five fiscal year before current	159,579		159,579		117,068
Revolving	0		0		0
Revolving converted to term loans	0		0		0
Loans, gross	1,109,810		1,109,810		1,267,936
Commercial Real Estate Portfolio Segment [Member] \| Special Mention [Member]
Current fiscal year	0		0		0
Fiscal year before current	0		0		0
Two fiscal year before current	0		0		9,280
Three fiscal year before current	0		0		0
Four fiscal year before current	7,778		7,778		0
Five fiscal year before current	4,904		4,904		0
Revolving	0		0		0
Revolving converted to term loans	0		0		0
Loans, gross	12,682		12,682		9,280
Commercial Real Estate Portfolio Segment [Member] \| Substandard [Member]
Current fiscal year	303		303		287
Fiscal year before current	9,800		9,800		0
Two fiscal year before current	0		0		8,652
Three fiscal year before current	11,514		11,514		2,329
Four fiscal year before current	2,303		2,303		222
Five fiscal year before current	17,798		17,798		23,426
Revolving	0		0		0
Revolving converted to term loans	0		0		0
Loans, gross	41,718		41,718		34,916
Commercial Real Estate Portfolio Segment [Member] \| Doubtful [Member]
Current fiscal year	0		0		0
Fiscal year before current	0		0		0
Two fiscal year before current	0		0		0
Three fiscal year before current	0		0		0
Four fiscal year before current	0		0		0
Five fiscal year before current	0		0		0
Revolving	0		0		0
Revolving converted to term loans	0		0		0
Loans, gross	0		0		0
Single Family Residential Mortgages Loans [Member]
Current fiscal year	147,380		147,380		637,893
Fiscal year before current	601,994		601,994		255,529
Two fiscal year before current	243,372		243,372		141,918
Three fiscal year before current	132,707		132,707		96,355
Four fiscal year before current	85,887		85,887		145,971
Five fiscal year before current	292,069		292,069		183,345
Revolving	1,898		1,898		3,097
Revolving converted to term loans	0		0		0
Loans, gross	1,505,307		1,505,307		1,464,108
YTD period charge-offs, current			(0)		(0)
YTD period charge-offs, one year before			(0)		(0)
YTD period charge-offs, two years before			(0)		(0)
YTD period charge-offs, three years before			93		(0)
YTD period charge-offs, four years before			(0)		(0)
YTD period charge-offs, prior			(0)		(0)
YTD period charge-offs, revolving			(0)		(0)
YTD period charge-offs, converted to term loan			(0)		(0)
YTD period charge-offs			93		(0)
YTD period recoveries, Current fiscal year	0		0		0
YTD period recoveries, Fiscal year before current	0		0		0
YTD period recoveries, Two fiscal year before current	0		0		0
YTD period recoveries, Three fiscal year before current	0		0		0
YTD period recoveries, Four fiscal year before current	0		0		0
YTD period recoveries, Five fiscal year before current	0		0		0
YTD period recoveries, Revolving	0		0		0
YTD period recoveries, Revolving converted to term loans			0		0
YTD period recoveries			0		0
Net, Current fiscal year	0		0		0
Net, Fiscal year before current	0		0		0
Net, Two fiscal year before current	0		0		0
Net, Three fiscal year before current	(93)		(93)		0
Net, Four fiscal year before current	0		0		0
Net, Five fiscal year before current	0		0		0
Net, Revolving	0		0		0
Net, Revolving converted to term loans			0		0
Net			(93)		0
Net recoveries (charge-offs), Current fiscal year	0		0		0
Single Family Residential Mortgages Loans [Member] \| Pass [Member]
Current fiscal year	147,380		147,380		637,893
Fiscal year before current	601,539		601,539		255,529
Two fiscal year before current	243,372		243,372		137,964
Three fiscal year before current	127,839		127,839		96,355
Four fiscal year before current	85,342		85,342		134,415
Five fiscal year before current	276,884		276,884		182,893
Revolving	1,813		1,813		2,992
Revolving converted to term loans	0		0		0
Loans, gross	1,484,169		1,484,169		1,448,041
Single Family Residential Mortgages Loans [Member] \| Special Mention [Member]
Current fiscal year	0		0		0
Fiscal year before current	0		0		0
Two fiscal year before current	0		0		0
Three fiscal year before current	0		0		0
Four fiscal year before current	0		0		3,925
Five fiscal year before current	3,862		3,862		0
Revolving	0		0		0
Revolving converted to term loans	0		0		0
Loans, gross	3,862		3,862		3,925
Single Family Residential Mortgages Loans [Member] \| Substandard [Member]
Current fiscal year	0		0		0
Fiscal year before current	455		455		0
Two fiscal year before current	0		0		3,954
Three fiscal year before current	4,868		4,868		0
Four fiscal year before current	545		545		7,631
Five fiscal year before current	11,323		11,323		452
Revolving	85		85		105
Revolving converted to term loans	0		0		0
Loans, gross	17,276		17,276		12,142
Single Family Residential Mortgages Loans [Member] \| Doubtful [Member]
Current fiscal year	0		0		0
Fiscal year before current	0		0		0
Two fiscal year before current	0		0		0
Three fiscal year before current	0		0		0
Four fiscal year before current	0		0		0
Five fiscal year before current	0		0		0
Revolving	0		0		0
Revolving converted to term loans	0		0		0
Loans, gross	0		0		0
Commercial and Industrial [Member]
Current fiscal year	1,524		1,524		8,038
Fiscal year before current	3,539		3,539		13,500
Two fiscal year before current	6,582		6,582		6,048
Three fiscal year before current	4,454		4,454		3,486
Four fiscal year before current	2,196		2,196		2,654
Five fiscal year before current	11,912		11,912		26,971
Revolving	97,448		97,448		140,440
Revolving converted to term loans	0		0		86
Loans, gross	127,655		127,655		201,223
YTD period charge-offs, current			(0)		(0)
YTD period charge-offs, one year before			(0)		(0)
YTD period charge-offs, two years before			(0)		(0)
YTD period charge-offs, three years before			(0)		5
YTD period charge-offs, four years before			(0)		(0)
YTD period charge-offs, prior			(0)		(0)
YTD period charge-offs, revolving			(0)		(0)
YTD period charge-offs, converted to term loan			(0)		(0)
YTD period charge-offs			(0)		5
YTD period recoveries, Current fiscal year	0		0		0
YTD period recoveries, Fiscal year before current	0		0		0
YTD period recoveries, Two fiscal year before current	0		0		0
YTD period recoveries, Three fiscal year before current	0		0		0
YTD period recoveries, Four fiscal year before current	0		0		0
YTD period recoveries, Five fiscal year before current	2		2		2
YTD period recoveries, Revolving	0		0		0
YTD period recoveries, Revolving converted to term loans			0		0
YTD period recoveries			2		2
Net, Current fiscal year	0		0		0
Net, Fiscal year before current	0		0		0
Net, Two fiscal year before current	0		0		0
Net, Three fiscal year before current	0		0		(5)
Net, Four fiscal year before current	0		0		0
Net, Five fiscal year before current	2		2		2
Net, Revolving	0		0		0
Net, Revolving converted to term loans			0		0
Net			2		(3)
Net recoveries (charge-offs), Current fiscal year	0		0		0
Commercial and Industrial [Member] \| Pass [Member]
Current fiscal year	1,524		1,524		8,038
Fiscal year before current	3,448		3,448		7,513
Two fiscal year before current	6,582		6,582		4,448
Three fiscal year before current	3,021		3,021		3,470
Four fiscal year before current	2,186		2,186		1,016
Five fiscal year before current	6,943		6,943		8,827
Revolving	93,638		93,638		129,483
Revolving converted to term loans	0		0		86
Loans, gross	117,342		117,342		162,881
Commercial and Industrial [Member] \| Special Mention [Member]
Current fiscal year	0		0		0
Fiscal year before current	0		0		5,987
Two fiscal year before current	0		0		0
Three fiscal year before current	0		0		0
Four fiscal year before current	0		0		1,638
Five fiscal year before current	0		0		17,805
Revolving	2,632		2,632		3,577
Revolving converted to term loans	0		0		0
Loans, gross	2,632		2,632		29,007
Commercial and Industrial [Member] \| Substandard [Member]
Current fiscal year	0		0		0
Fiscal year before current	91		91		0
Two fiscal year before current	0		0		1,600
Three fiscal year before current	1,433		1,433		16
Four fiscal year before current	10		10		0
Five fiscal year before current	4,969		4,969		339
Revolving	1,175		1,175		7,380
Revolving converted to term loans	0		0		0
Loans, gross	7,678		7,678		9,335
Commercial and Industrial [Member] \| Doubtful [Member]
Current fiscal year	0		0		0
Fiscal year before current	0		0		0
Two fiscal year before current	0		0		0
Three fiscal year before current	0		0		0
Four fiscal year before current	0		0		0
Five fiscal year before current	0		0		0
Revolving	3		3		0
Revolving converted to term loans	0		0		0
Loans, gross	3		3		0
SBA Loans [Member]
Current fiscal year	2,812		2,812		14,922
Fiscal year before current	11,066		11,066		10,664
Two fiscal year before current	10,476		10,476		6,496
Three fiscal year before current	3,079		3,079		4,779
Four fiscal year before current	4,692		4,692		3,596
Five fiscal year before current	18,295		18,295		20,954
Revolving	0		0		0
Revolving converted to term loans	0		0		0
Loans, gross	50,420		50,420		61,411
YTD period charge-offs, current			(0)		(0)
YTD period charge-offs, one year before			(0)		(0)
YTD period charge-offs, two years before			(0)		(0)
YTD period charge-offs, three years before			(0)		(0)
YTD period charge-offs, four years before			(0)		(0)
YTD period charge-offs, prior			62		14
YTD period charge-offs, revolving			(0)		(0)
YTD period charge-offs, converted to term loan			(0)		(0)
YTD period charge-offs			62		14
YTD period recoveries, Current fiscal year	0		0		0
YTD period recoveries, Fiscal year before current	0		0		0
YTD period recoveries, Two fiscal year before current	0		0		0
YTD period recoveries, Three fiscal year before current	0		0		0
YTD period recoveries, Four fiscal year before current	0		0		0
YTD period recoveries, Five fiscal year before current	0		0		227
YTD period recoveries, Revolving	0		0		0
YTD period recoveries, Revolving converted to term loans			0		0
YTD period recoveries			0		227
Net, Current fiscal year	0		0		0
Net, Fiscal year before current	0		0		0
Net, Two fiscal year before current	0		0		0
Net, Three fiscal year before current	0		0		0
Net, Four fiscal year before current	0		0		0
Net, Five fiscal year before current	(62)		(62)		213
Net, Revolving	0		0		0
Net, Revolving converted to term loans			0		0
Net			(62)		213
Net recoveries (charge-offs), Current fiscal year	0		0		0
SBA Loans [Member] \| Pass [Member]
Current fiscal year	2,812		2,812		14,922
Fiscal year before current	11,066		11,066		10,664
Two fiscal year before current	10,146		10,146		6,496
Three fiscal year before current	3,079		3,079		4,688
Four fiscal year before current	4,607		4,607		2,579
Five fiscal year before current	13,934		13,934		16,793
Revolving	0		0		0
Revolving converted to term loans	0		0		0
Loans, gross	45,644		45,644		56,142
SBA Loans [Member] \| Special Mention [Member]
Current fiscal year	0		0		0
Fiscal year before current	0		0		0
Two fiscal year before current	330		330		0
Three fiscal year before current	0		0		0
Four fiscal year before current	0		0		0
Five fiscal year before current	0		0		0
Revolving	0		0		0
Revolving converted to term loans	0		0		0
Loans, gross	330		330		0
SBA Loans [Member] \| Substandard [Member]
Current fiscal year	0		0		0
Fiscal year before current	0		0		0
Two fiscal year before current	0		0		0
Three fiscal year before current	0		0		91
Four fiscal year before current	85		85		1,017
Five fiscal year before current	4,361		4,361		4,161
Revolving	0		0		0
Revolving converted to term loans	0		0		0
Loans, gross	4,446		4,446		5,269
SBA Loans [Member] \| Doubtful [Member]
Current fiscal year	0		0		0
Fiscal year before current	0		0		0
Two fiscal year before current	0		0		0
Three fiscal year before current	0		0		0
Four fiscal year before current	0		0		0
Five fiscal year before current	0		0		0
Revolving	0		0		0
Revolving converted to term loans	0		0		0
Loans, gross	0		0		0
Other Loans [Member]
Current fiscal year	204		204		4,329
Fiscal year before current	3,113		3,113		14,732
Two fiscal year before current	9,362		9,362		1,515
Three fiscal year before current	847		847		90
Four fiscal year before current	39		39		7
Five fiscal year before current	0		0		0
Revolving	17		17		26
Revolving converted to term loans	0		0		0
Loans, gross	13,582		13,582		20,699
YTD period charge-offs, current			(0)		(0)
YTD period charge-offs, one year before			79		237
YTD period charge-offs, two years before			199		(0)
YTD period charge-offs, three years before			10		(0)
YTD period charge-offs, four years before			(0)		(0)
YTD period charge-offs, prior			(0)		(0)
YTD period charge-offs, revolving			(0)		(0)
YTD period charge-offs, converted to term loan			(0)		(0)
YTD period charge-offs			288		237
YTD period recoveries, Current fiscal year	0		0		0
YTD period recoveries, Fiscal year before current	0		0		27
YTD period recoveries, Two fiscal year before current	46		46		2
YTD period recoveries, Three fiscal year before current	1		1		0
YTD period recoveries, Four fiscal year before current	0		0		0
YTD period recoveries, Five fiscal year before current	0		0		0
YTD period recoveries, Revolving	0		0		0
YTD period recoveries, Revolving converted to term loans			0		0
YTD period recoveries			47		29
Net, Current fiscal year	0		0		0
Net, Fiscal year before current	(79)		(79)		(210)
Net, Two fiscal year before current	(153)		(153)		2
Net, Three fiscal year before current	(9)		(9)		0
Net, Four fiscal year before current	0		0		0
Net, Five fiscal year before current	0		0		0
Net, Revolving	0		0		0
Net, Revolving converted to term loans			0		0
Net			(241)		(208)
Net recoveries (charge-offs), Current fiscal year	0		0		0
Other Loans [Member] \| Pass [Member]
Current fiscal year	204		204		4,224
Fiscal year before current	3,002		3,002		14,684
Two fiscal year before current	9,326		9,326		1,505
Three fiscal year before current	839		839		90
Four fiscal year before current	39		39		7
Five fiscal year before current	0		0		0
Revolving	17		17		26
Revolving converted to term loans	0		0		0
Loans, gross	13,427		13,427		20,536

The recoveries in current fiscal year for allowance for credit loss on financing receivable.

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The recoveries in fiscal year before current fiscal year for allowance for credit loss on financing receivable.

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The recoveries in five fiscal years before current fiscal year for allowance for credit loss on financing receivable.

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The recoveries in four fiscal years before current fiscal year for allowance for credit loss on financing receivable.

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The recoveries in allowance for credit loss on revolving financing receivable.

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The recoveries in three fiscal years before current fiscal year for allowance for credit loss on financing receivable.

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The recoveries in two fiscal year before current fiscal year for allowance for credit loss on financing receivable.

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The net recoveries (write-off) of financing receivable originated in two fiscal years before current fiscal year.

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Amount of increase in allowance for credit loss on financing receivable converted to term loan from recovery.

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Amount, after recovery, of writeoff of financing receivable converted to term loan, charged against allowance for credit loss.

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Amortized cost of financing receivable originated more than five years prior to current fiscal year. Excludes net investment in lease.

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Amortized cost of financing receivable originated four years prior to current fiscal year. Excludes net investment in lease.

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Amount of writeoff of financing receivable originated more than five years before current fiscal year. Excludes net investment in lease.

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Amount of writeoff of financing receivable originated in fiscal year before current fiscal year. Excludes net investment in lease.

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