XML 142 R129.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Subsequent Events - Additional Information (Detail) - $ / shares |  |  | 1 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
May 02, 2018 | May 01, 2018 | May 01, 2018 | Mar. 31, 2018 | Mar. 31, 2017 | Dec. 31, 2017
Class A Common Stock [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Common stock, issued during the period |  |  |  | 18,925,702 |  | 1,994,670
Class A Common Stock [Member] | Subsequent Event [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Dividend declared per share |  | $ 0.18 | $ 0.18 |  |  |
Dividend payable declared date |  | May 01, 2018 |  |  |  |
Dividend payable, date to be paid |  | Jun. 05, 2018 |  |  |  |
Dividend payable record date |  | May 21, 2018 |  |  |  |
Class B Common Stock [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Common stock, issued during the period |  |  |  | 0 | 0 |
Class B Common Stock [Member] | Subsequent Event [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Dividend declared per share |  | $ 0.18 | $ 0.18 |  |  |
Dividend payable declared date |  | May 01, 2018 |  |  |  |
Dividend payable, date to be paid |  | Jun. 05, 2018 |  |  |  |
Dividend payable record date |  | May 21, 2018 |  |  |  |
Newmark [Member] | Class A Common Stock [Member] | Subsequent Event [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Dividend declared per share | $ 0.09 |  |  |  |  |
Dividend payable declared date | May 02, 2018 |  |  |  |  |
Dividend payable, date to be paid | Jun. 05, 2018 |  |  |  |  |
Dividend payable record date | May 21, 2018 |  |  |  |  |
Newmark [Member] | Class B Common Stock [Member] | Subsequent Event [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Dividend declared per share | $ 0.09 |  |  |  |  |
Dividend payable declared date | May 02, 2018 |  |  |  |  |
Dividend payable, date to be paid | Jun. 05, 2018 |  |  |  |  |
Dividend payable record date | May 21, 2018 |  |  |  |  |
Controlled Equity Offerings [Member] | Class A Common Stock [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Common stock, issued during the period |  |  | 3,200,000 |  |  |

X
- Definition Date the declared dividend will be paid, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586 + Details
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- Definition The per share amount of a dividend declared, but not paid, as of the financial reporting date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586 + Details
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- Definition Date the dividend to be paid was declared, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586 + Details
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- Definition Number of new stock issued during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21463-112644 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 4: http://www.xbrl.org/2003/role/presentationRef -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 + Details
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- Definition Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event. + References No definition available. + Details
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