Committed Lines of Credit (Tables)

3 Months Ended

Mar. 31, 2018

Short-term Debt [Abstract]

Schedule of Line of Credit Facilities [Table Text Block]

outstanding and interest rates of borrowings (excluding letters of credit) under the Company’s revolving committed line of credit were as follows as of March 31, 2018 and December 31, 2017 (dollars in thousands):

	March 31,			December 31,
	2018			2017
Balance outstanding at end of period (1)	$	50,000		$	105,000
Letters of credit outstanding at end of period	$	35,420		$	34,420
Average interest rate at end of period	2.56		%	2.26		%