CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
Unrealized gains on available-for-sale securities, taxes	$ 0	$ 183	$ 208
Reclassification adjustment for gains on available-for-sale securities included in net income, taxes	0	508	0
Unfunded pension liability, taxes	$ 7	$ 248	$ 123