Stockholders' Equity (Summary of Regular Quarterly Dividend) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash dividend (in usd per share)	$ 0.65	$ 0.65	$ 0.65	$ 0.65	$ 0.60	$ 2.55
Payment of dividends	$ 16,321				$ 14,999
Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payment of dividends	$ 16,321	$ 16,280	$ 16,267	$ 16,267	$ 14,999	$ 63,813

Aggregate dividends paid during the period for each share of common stock outstanding.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
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No definition available.

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