At Market stock offering program remained available for issuance.

No definition available.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

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Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended
	Apr. 17, 2019	Mar. 31, 2019	Mar. 31, 2018	May 07, 2019	Apr. 30, 2019	Dec. 31, 2018
Subsequent Event [Line Items]
Payment of dividend		$ 46,996	$ 43,033
Common stock, shares issued (in shares)		100,967,024				100,746,988
Subsequent event [Member]
Subsequent Event [Line Items]
Payment of dividend	$ 47,600
Subsequent event [Member] \| Common Stock [Member] \| At-The-Market Program [Member]
Subsequent Event [Line Items]
Common stock, shares issued (in shares)					325,710
Price per share (in dollars per share)					$ 76.39
At the market stock offering remaining amount available for issuance				$ 375,000