Benefit Plans - Deferred Stock Rights (Details)	9 Months Ended
Sep. 30, 2017 shares
Deferred Stock Rights
Outstanding, beginning of period	82,377
Granted	463
Exercised	0
Outstanding, end of period	82,840

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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Balance Type:	na
Period Type:	duration