Consolidated Statements of Income (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Consolidated Statements of Income
Impairment charges, other-than-temporary impairment charges	$ 1,325	$ (366)	$ (431)
Impairment charges, other comprehensive (income) loss	$ (371)	$ 1,183	$ (1,805)

Amount before tax, after reclassification adjustments of other comprehensive income (loss).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669625-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=35755396&loc=d3e33775-111570

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669619-108580

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