Earnings per Share - Summary of Components used in Calculation of Basic and Diluted Earnings per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2017 |
Sep. 30, 2017 |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2016 |
Sep. 30, 2016 |
Jun. 30, 2016 |
Mar. 31, 2016 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
|
| Basic earnings: | |||||||||||
| Net earnings attributable to Broadstone Net Lease, Inc | $ 15,530 | $ 11,948 | $ 14,727 | $ 12,594 | $ 12,480 | $ 13,958 | $ 4,818 | $ 5,098 | $ 54,799 | $ 36,354 | $ 19,287 |
| Diluted earnings: | |||||||||||
| Net earnings attributable to Broadstone Net Lease, Inc | 15,530 | 11,948 | 14,727 | 12,594 | 12,480 | 13,958 | 4,818 | 5,098 | 54,799 | 36,354 | 19,287 |
| Net earnings attributable to non-controlling interests | $ 1,296 | $ 1,042 | $ 1,265 | $ 1,153 | $ 1,314 | $ 1,459 | $ 538 | $ 603 | 4,756 | 3,914 | 1,603 |
| Net income (loss) attributable to parent, Diluted | $ 59,555 | $ 40,268 | $ 20,890 | ||||||||
| Basic and diluted weighted average shares outstanding: | |||||||||||
| Basic | 18,515 | 17,617 | 16,623 | 15,582 | 14,497 | 13,647 | 12,766 | 11,802 | 17,084 | 13,178 | 8,989 |
| Effects of convertible membership units | 1,483 | 1,419 | 747 | ||||||||
| Weighted average number of common shares outstanding used in diluted earnings per share | 20,096 | 19,147 | 18,051 | 17,009 | 15,924 | 15,074 | 14,193 | 13,196 | 18,567 | 14,597 | 9,736 |
| Basic and diluted | $ 0.84 | $ 0.68 | $ 0.89 | $ 0.81 | $ 0.86 | $ 1.02 | $ 0.38 | $ 0.43 | $ 3.21 | $ 2.76 | $ 2.15 |