Marketable Investment Securities, Restricted Cash and Cash Equivalents, and Other Investment Securities (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Mar. 31, 2021	Dec. 31, 2019	Feb. 28, 2017
Marketable Investment Securities, Restricted Cash and Cash Equivalents and Other Investment Securities:
Current marketable investment securities	$ 132,593	$ 48,995
Restricted marketable investment securities			$ 390
Total marketable investment securities	132,593	48,995	390
Restricted cash and cash equivalents	58,323	58,255	60,677
Other investment securities	97,306	98,050	106,874
Total other investment securities	97,306	98,050	106,874
Total marketable investment securities, restricted cash and cash equivalents, and other investment securities	$ 288,222	$ 205,300	$ 167,941
Maximum maturities of commercial paper	365 days
Maximum maturities of corporate securities	18 months
NagraStar L.L.C
Marketable Investment Securities, Restricted Cash and Cash Equivalents and Other Investment Securities:
Ownership interest in equity method investment				50.00%
NagraStar L.L.C
Marketable Investment Securities, Restricted Cash and Cash Equivalents and Other Investment Securities:
Ownership interest in equity method investment	50.00%			50.00%

Maximum maturities of commercial paper.

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Maximum maturities of corporate securities.

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Marketable investment securities, restricted cash and cash equivalent and other investment securities.

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The amount of marketable securities pledged as collateral noncurrent.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount of investment in marketable security.

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Amount of investment in marketable security, classified as current.

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Amount of investments classified as other.

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Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, 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.

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