CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Interest rate swaps, deferred tax expense	$ 100	$ 200	$ (1,300)	$ (8,100)
Capitalized swap interest, deferred tax benefit			$ (100)	(100)
Pension adjustment, tax		$ (100)		$ (543)