Shareholder Report, Average Annual Return (Details) |
12 Months Ended | 60 Months Ended | 115 Months Ended |
|---|---|---|---|
May 31, 2026 |
May 31, 2026 |
May 31, 2026 |
|
| Without Sales Load [Member] | C000174964 | |||
| Average Annual Return [Line Items] | |||
| Average Annual Return, Percent | 5.41% | (0.13%) | 2.20% |
| Without Sales Load [Member] | C000174965 | |||
| Average Annual Return [Line Items] | |||
| Average Annual Return, Percent | 5.10% | (0.42%) | 1.90% |
| Without Sales Load [Member] | C000174966 | |||
| Average Annual Return [Line Items] | |||
| Average Annual Return, Percent | 5.55% | 0.01% | 2.32% |
| Bloomberg U.S. Aggregate Bond Index | |||
| Average Annual Return [Line Items] | |||
| Average Annual Return, Percent | 5.13% | 0.17% | 1.83% |
| Bloomberg U.S. Aggregate Bond Index | |||
| Average Annual Return [Line Items] | |||
| Average Annual Return, Percent | 5.13% | 0.17% | 1.83% |
| Bloomberg U.S. Aggregate Bond Index | |||
| Average Annual Return [Line Items] | |||
| Average Annual Return, Percent | 5.13% | 0.17% | 1.83% |