9. Mortgage Banking

Net revenues from the sales and servicing of mortgage loans consisted of the following:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2019		2018		2019		2018
	(In Thousands)
Gain from sale of mortgage loans	$	1,775	$	1,383	$	3,076	$	2,464
Mortgage loans servicing revenue (expense):
Mortgage loans servicing revenue		943		933		1,882		1,877
Amortization of mortgage servicing rights		(391)		(350)		(677)		(669)
Mortgage servicing rights valuation adjustments		(190)		47		(303)		83
		362		630		902		1,291

Net revenue from sale and servicing of mortgage loans	$	2,137	$	2,013	$	3,978	$	3,755

The unpaid principal balance of residential mortgage loans serviced for third parties was $1.42 billion at June 30, 2019 and $1.41 billion at December 31, 2018.

Activity for capitalized mortgage servicing rights and the related valuation allowance follows for the three and six months ended June 30, 2019 and 2018:


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2019		2018		2019		2018
	(In Thousands)
Mortgage servicing assets:
Balance at beginning of period	$	10,411	$	10,245	$	10,419	$	10,240
Loans sold, servicing retained		438		402		716		726
Amortization		(391)		(350)		(677)		(669)
Carrying value before valuation allowance at end of period		10,458		10,297		10,458		10,297

Valuation allowance:
Balance at beginning of period		(413)		(396)		(300)		(432)
Impairment recovery (charges)		(190)		47		(303)		83
Balance at end of period		(603)		(349)		(603)		(349)
Net carrying value of MSRs at end of period	$	9,855	$	9,948	$	9,855	$	9,948
Fair value of MSRs at end of period	$	9,925	$	10,488	$	9,925	$	10,488

Amortization of mortgage servicing rights is computed based on payments and payoffs of the related mortgage loans serviced. Estimates of future amortization expense are not easily estimable.

The Company has established an accrual for secondary market buy-back activity. A liability of $43,000 was accrued at both June 30, 2019, and December 31, 2018, respectively. There was no expense or credit recognized related to the accrual in the three or six months ended June 30, 2019 or 2018.