v3.26.1
Shareholder Report, Line Graph (Details) - USD ($)
 1 Months Ended 4 Months Ended 7 Months Ended 10 Months Ended 13 Months Ended 16 Months Ended 19 Months Ended 22 Months Ended 25 Months Ended 28 Months Ended 31 Months Ended 34 Months Ended 37 Months Ended 40 Months Ended 43 Months Ended 46 Months Ended 49 Months Ended 52 Months Ended 55 Months Ended 58 Months Ended 61 Months Ended 64 Months Ended 67 Months Ended 70 Months Ended 73 Months Ended 76 Months Ended 79 Months Ended 82 Months Ended 85 Months Ended 88 Months Ended 91 Months Ended 94 Months Ended 97 Months Ended 100 Months Ended 103 Months Ended 106 Months Ended 109 Months Ended 112 Months Ended 115 Months Ended
Nov. 15, 2016
Nov. 30, 2016
Feb. 28, 2017
May 31, 2017
Aug. 31, 2017
Nov. 30, 2017
Feb. 28, 2018
May 31, 2018
Aug. 31, 2018
Nov. 30, 2018
Feb. 28, 2019
May 31, 2019
Aug. 31, 2019
Nov. 30, 2019
Feb. 29, 2020
May 31, 2020
Aug. 31, 2020
Nov. 30, 2020
Feb. 28, 2021
May 31, 2021
Aug. 31, 2021
Nov. 30, 2021
Feb. 28, 2022
May 31, 2022
Aug. 31, 2022
Nov. 30, 2022
Feb. 28, 2023
May 31, 2023
Aug. 31, 2023
Nov. 30, 2023
Feb. 29, 2024
May 31, 2024
Aug. 31, 2024
Nov. 30, 2024
Feb. 28, 2025
May 31, 2025
Aug. 31, 2025
Nov. 30, 2025
Feb. 28, 2026
May 31, 2026
C000174964                                                                                
Account Value [Line Items]                                                                                
Accumulated Value $ 10,000 $ 9,937 $ 10,067 $ 10,263 $ 10,418 $ 10,413 $ 10,327 $ 10,367 $ 10,417 $ 10,324 $ 10,647 $ 11,056 $ 11,482 $ 11,485 $ 11,851 $ 11,715 $ 12,228 $ 12,395 $ 12,350 $ 12,381 $ 12,641 $ 12,575 $ 12,163 $ 11,268 $ 10,985 $ 10,617 $ 10,709 $ 10,852 $ 10,725 $ 10,741 $ 11,000 $ 11,027 $ 11,574 $ 11,578 $ 11,745 $ 11,671 $ 11,980 $ 12,247 $ 12,455 $ 12,302
C000174965                                                                                
Account Value [Line Items]                                                                                
Accumulated Value 10,000 9,936 10,056 10,243 10,388 10,375 10,284 10,317 10,358 10,259 10,572 10,970 11,383 11,379 11,733 11,590 12,089 12,245 12,192 12,214 12,472 12,387 11,972 11,083 10,809 10,427 10,523 10,643 10,511 10,532 10,778 10,784 11,323 11,320 11,460 11,381 11,674 11,925 12,133 11,962
C000174966                                                                                
Account Value [Line Items]                                                                                
Accumulated Value 500,000 496,851 503,363 513,256 521,056 520,933 516,856 519,026 522,174 517,720 533,443 554,123 575,568 576,503 595,034 588,368 613,717 622,323 620,290 622,099 635,958 632,907 611,769 566,964 553,535 534,537 539,983 546,764 540,523 541,527 555,425 556,327 584,780 585,222 593,124 589,617 605,442 619,109 630,587 622,343
Bloomberg U.S. Aggregate Bond Index                                                                                
Account Value [Line Items]                                                                                
Accumulated Value 10,000 9,951 10,051 10,201 10,327 10,270 10,102 10,163 10,218 10,133 10,422 10,814 11,258 11,226 11,640 11,832 11,987 12,044 11,801 11,784 11,977 11,905 11,489 10,815 10,597 10,376 10,372 10,583 10,471 10,499 10,717 10,722 11,235 11,220 11,340 11,307 11,587 11,860 12,049 11,887
Bloomberg U.S. Aggregate Bond Index                                                                                
Account Value [Line Items]                                                                                
Accumulated Value 10,000 9,951 10,051 10,201 10,327 10,270 10,102 10,163 10,218 10,133 10,422 10,814 11,258 11,226 11,640 11,832 11,987 12,044 11,801 11,784 11,977 11,905 11,489 10,815 10,597 10,376 10,372 10,583 10,471 10,499 10,717 10,722 11,235 11,220 11,340 11,307 11,587 11,860 12,049 11,887
Bloomberg U.S. Aggregate Bond Index                                                                                
Account Value [Line Items]                                                                                
Accumulated Value $ 500,000 $ 497,530 $ 502,564 $ 510,073 $ 516,343 $ 513,521 $ 505,103 $ 508,162 $ 510,924 $ 506,629 $ 521,113 $ 540,686 $ 562,898 $ 561,300 $ 581,993 $ 591,595 $ 599,337 $ 602,185 $ 590,046 $ 589,200 $ 598,831 $ 595,239 $ 574,444 $ 540,756 $ 529,870 $ 518,813 $ 518,597 $ 529,168 $ 523,548 $ 524,934 $ 535,852 $ 536,077 $ 561,749 $ 561,023 $ 566,975 $ 565,341 $ 579,367 $ 593,009 $ 602,471 $ 594,361