Stockholders' Equity Issuance of Common Stock in Connection with Acquisition of CYS Investments, Inc. (Details) - USD ($) $ in Millions |
1 Months Ended | 12 Months Ended | |||
|---|---|---|---|---|---|
Mar. 22, 2019 |
Jul. 31, 2018 |
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
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| Class of Stock [Line Items] | |||||
| Number of shares of stock issued during period (in shares) | 26,950 | ||||
| Aggregate cash consideration exchanged for shares of CYS common stock | $ 15.0 | ||||
| Common Stock [Member] | |||||
| Class of Stock [Line Items] | |||||
| Number of shares of stock issued during period (in shares) | 18,000,000 | 72,600,000 | 24,439,436 | 72,616,483 | |
| X | ||||||||||
- Definition Aggregate cash consideration exchanged for shares of CYS common stock. No definition available.
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- Definition 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. No definition available.
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- Definition Number of new stock issued during the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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