11. MORTGAGE BANKING ACTIVITIES

Activity for mortgage loans held for sale, at fair value, was as follows:


	Three Months Ended				Nine Months Ended
	September 30,				September 30,
(in thousands)	2016		2015		2016		2015

Balance, beginning of period	$	12,280	$	10,277	$	4,083	$	6,388
Origination of mortgage loans held for sale		58,820		32,018		154,607		128,026
Transferred from held for investment to held for sale		71,201		—		71,201		—
Proceeds from the sale of mortgage loans held for sale		(136,946)		(34,605)		(227,096)		(129,077)
Net gain on sale of mortgage loans held for sale		3,087		836		5,647		3,189
Balance, end of period	$	8,442	$	8,526	$	8,442	$	8,526

The following table presents the components of Mortgage Banking income:


	Three Months Ended				Nine Months Ended
	September 30,				September 30,
(in thousands)	2016		2015		2016		2015

Net gain realized on sale of mortgage loans held for sale	$	1,754	$	926	$	3,861	$	3,024
Net gain realized on sale of mortgage loans transferred from held for investment to held for sale during the period		1,129		—		1,129		—
Net change in fair value recognized on loans held for sale		57		10		155		107
Net change in fair value recognized on rate lock commitments		69		(37)		604		89
Net change in fair value recognized on forward contracts		78		(63)		(102)		(31)
Net gain recognized		3,087		836		5,647		3,189

Loan servicing income		511		477		1,455		1,417
Amortization of mortgage servicing rights		(517)		(341)		(1,200)		(1,057)
Net servicing income recognized		(6)		136		255		360
Total Mortgage Banking income	$	3,081	$	972	$	5,902	$	3,549

Activity for capitalized mortgage servicing rights was as follows:


	Three Months Ended				Nine Months Ended
	September 30,				September 30,
(in thousands)	2016		2015		2016		2015

Balance, beginning of period	$	4,998	$	4,971	$	4,912	$	4,813
Additions		857		338		1,626		1,212
Amortized to expense		(517)		(341)		(1,200)		(1,057)
Balance, end of period	$	5,338	$	4,968	$	5,338	$	4,968

There was no balance or activity in the valuation allowance for capitalized mortgage servicing rights for the three and nine months ended September 30, 2016 and 2015.

Other information relating to mortgage servicing rights follows:


(dollars in thousands)	September 30, 2016		December 31, 2015

Fair value of mortgage servicing rights portfolio	$	6,868	$	7,242
Monthly prepayment rate of unpaid principal balance*		108% - 456%		105% - 369%
Discount rate		12%		10%
Weighted average default rate		1.50%		1.50%
Weighted average life in years		5.56		6.38

* Rates are applied to individual tranches with similar characteristics.

Mortgage Banking derivatives used in the ordinary course of business primarily consist of mandatory forward sales contracts and interest rate lock loan commitments. Mandatory forward contracts represent future commitments to deliver loans at a specified price and date and are used to manage interest rate risk on loan commitments and mortgage loans held for sale. Interest rate lock loan commitments represent commitments to fund loans at a specific rate. These derivatives involve underlying items, such as interest rates, and are designed to transfer risk. Substantially all of these instruments expire within 90 days from the date of issuance. Notional amounts are amounts on which calculations and payments are based, but which do not represent credit exposure, as credit exposure is limited to the amounts required to be received or paid.

Mandatory forward contracts also contain an element of risk in that the counterparties may be unable to meet the terms of such agreements. In the event the counterparties fail to deliver commitments or are unable to fulfill their obligations, the Bank could potentially incur significant additional costs by replacing the positions at then current market rates. The Bank manages its risk of exposure by limiting counterparties to those banks and institutions deemed appropriate by management and the Board of Directors. The Bank does not expect any counterparty to default on their obligations and therefore, the Bank does not expect to incur any cost related to counterparty default.

The Bank is exposed to interest rate risk on loans held for sale and rate lock loan commitments. As market interest rates fluctuate, the fair value of mortgage loans held for sale and rate lock commitments will decline or increase. To offset this interest rate risk the Bank enters into derivatives, such as mandatory forward contracts to sell loans. The fair value of these mandatory forward contracts will fluctuate as market interest rates fluctuate, and the change in the value of these instruments is expected to largely, though not entirely, offset the change in fair value of loans held for sale and rate lock commitments. The objective of this activity is to minimize the exposure to losses on rate-loan lock commitments and loans held for sale due to market interest rate fluctuations. The net effect of derivatives on earnings will depend on risk management activities and a variety of other factors, including: market interest rate volatility; the amount of rate lock commitments that close; the ability to fill the forward contracts before expiration; and the time period required to close and sell loans.

The following table includes the notional amounts and fair values of mortgage loans held for sale at fair value and mortgage banking derivatives as of the period ends presented:


	September 30, 2016				December 31, 2015
	Notional				Notional
(in thousands)	Amount		Fair Value		Amount		Fair Value

Included in Mortgage loans held for sale:
Mortgage loans held for sale, at fair value	$	8,197	$	8,442	$	3,993	$	4,083

Included in other assets:
Rate lock loan commitments	$	39,683	$	910	$	21,580	$	306

Included in other liabilities:
Mandatory forward contracts	$	40,056	$	130	$	19,232	$	25