An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Expected Long-Term Rate of Return on Plan Assets
-URI http://asc.fasb.org/extlink&oid=6512046

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
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Target allocation of investments of this type to total plan assets presented on a weighted average basis.

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-SubTopic 20
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Benefit Plans - Plan Assets Allocation (Details) - Pension Plan	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Benefit plans
Asset Allocation (as a percent)	100.00%	100.00%
Expected long term return on plan assets (as a percent)	5.50%	4.50%	4.50%
Equity securities
Benefit plans
Asset Allocation (as a percent)	28.00%	40.00%
Target Allocation (as a percent)	28.00%
FHI stock
Benefit plans
Asset Allocation (as a percent)	0.00%	0.00%
BNP Paribas stock
Benefit plans
Asset Allocation (as a percent)	0.00%	0.00%
Debt securities
Benefit plans
Asset Allocation (as a percent)	62.00%	55.00%
Target Allocation (as a percent)	64.00%
Other securities
Benefit plans
Asset Allocation (as a percent)	10.00%	5.00%
Target Allocation (as a percent)	8.00%