Subsequent Events (Details) - Senior Note - USD ($)	Oct. 28, 2016	May 02, 2016
3.25% Senior Notes Due 2031 \| Subsequent Event
Subsequent Event [Line Items]
Debt issued		$ 50,000,000
Interest rate		3.65%
Scenario, Forecast [Member] \| 3.72% Senior Notes Due 2031
Subsequent Event [Line Items]
Debt issued	$ 50,000,000
Interest rate	3.72%

Face (par) amount of debt instrument at time of issuance.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant