[Line Items] for Disclosures of organization, consolidation and basis of presentation of financial statements.

No definition available.

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- Definition

Amount of short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

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- Definition

Amount of lessee's right to use underlying asset under operating lease.

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- Definition

Amount of each individual error being corrected in the correcting adjustment.

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

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Number of shares that have been repurchased during the period and are being held in treasury.

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- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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Summary of Significant Accounting Policies (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2019	Jan. 01, 2019	Dec. 31, 2018	Nov. 30, 2018
Organization Consolidation And Presentation [Line Items]
Cash equivalents			$ 156,900		$ 146,100
Share repurchase program authorized						$ 75,000
Repurchases of common stock under share repurchase program (shares)			1.0
Weighted average cost of repurchased shares			$ 17.11
Repurchases of common stock under share repurchase program	$ 737	$ 15,709	$ 16,400
Remaining under current repurchase authorization			55,700
Operating lease right-of-use assets			125,093	$ 110,000	$ 0
Operating lease liability			131,841	$ 115,000
Bad Debt Reserve [Member] \| Selling, General and Administrative Expenses [Member]
Organization Consolidation And Presentation [Line Items]
Prior period adjustment			4,300
Bad Debt Reserve [Member] \| Accounts Receivable [Member]
Organization Consolidation And Presentation [Line Items]
Prior period adjustment			$ (4,300)