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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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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- Definition

Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Capital Stock - Summary of Cash Dividends Declared (Details) - USD ($)																									12 Months Ended
	Dec. 31, 2019	Nov. 05, 2019	Sep. 30, 2019	Jul. 30, 2019	Jun. 28, 2019	Apr. 30, 2019	Mar. 29, 2019	Feb. 20, 2019	Dec. 28, 2018	Nov. 07, 2018	Sep. 28, 2018	Aug. 01, 2018	Jun. 29, 2018	May 01, 2018	Mar. 30, 2018	Feb. 22, 2018	Dec. 28, 2017	Nov. 01, 2017	Sep. 29, 2017	Aug. 01, 2017	Jun. 30, 2017	May 02, 2017	Mar. 31, 2017	Feb. 14, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend declared per share (in dollars per share)		$ 0.30		$ 0.30		$ 0.30		$ 0.30		$ 0.30		$ 0.30		$ 0.30		$ 0.30				$ 0.30		$ 0.30		$ 0.30	$ 1.20	$ 1.20	$ 1.70
Total Amount	$ 9,228,656		$ 9,230,801		$ 9,204,804		$ 9,146,357		$ 9,088,542		$ 9,080,519		$ 9,066,023		$ 9,049,476				$ 8,943,279		$ 8,917,471		$ 8,878,147		$ 36,810,618	$ 36,284,560	$ 50,670,087
November 1, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend declared per share (in dollars per share)																		$ 0.30
Total Amount																	$ 8,974,196
November 1, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend declared per share (in dollars per share)																		$ 0.50
Total Amount																	$ 14,956,994