Commitments, Off-Balance Sheet Arrangements, and Contingent Liabilities (Tables)
 3 Months Ended
Mar. 31, 2018
Commitments, Off-Balance Sheet Arrangements, and Contingent Liabilities [Abstract]  
Financial Instruments with Off-Balance Sheet Risk
The Company is a party to financial instruments with off-balance-sheet risk in the normal course of business to meet the financing needs of its customers. These financial instruments include commitments to extend credit and standby letters of credit. Those instruments involve, to varying degrees, elements of credit and interest rate risk in excess of the amounts recognized in the consolidated statements of financial condition. The contract or notional amounts of those instruments reflect the extent of involvement the Company has in particular classes of financial instruments.

  
March 31, 2018
  
December 31, 2017
 
  
(In Thousands)
 
Financial instruments whose contract amounts represent potential credit risk:
      
Commitments to extend credit under amortizing loans (1)
 
$
53,445
  
$
31,543
 
Commitments to extend credit under home equity lines of credit (2)
  
15,080
   
14,972
 
Unused portion of construction loans (3)
  
24,194
   
17,097
 
Unused portion of business lines of credit
  
16,078
   
16,878
 
Standby letters of credit
  
267
   
259
 

(1) Commitments for loans are extended to customers for up to 90 days after which they expire. Excludes commitments to originate loans held for sale, which are discussed in the following footnote.
(2)  Unused portions of home equity loans are available to the borrower for up to 10 years.
(3)  Unused portions of construction loans are available to the borrower for up to one year.