Net Assets Investment Company, Portfolio Turnover C000145193 [Member] Schwab Fundamental Global Real Estate Index Fund FTSE EPRA Nareit Global Index (Net) [Member] Fundamental Global Real Estate Spliced Index [Member] RAFI Fundamental High Liquidity Global Real Estate Index (Net) [Member] MSCI ACWI Index (Net) [Member] AUSTRALIA CHINA HONG KONG JAPAN UNITED STATES Other Countries [Member] Data Center REITs [Member] Diversified Real Estate Activities [Member] Diversified REITs [Member] Health Care REITs [Member] Hotel & Resort REITs [Member] Industrial Conglomerates [Member] Industrial REITs [Member] Investment Companies [Member] Multi-Family Residential REITs [Member] Office REITs [Member] Other [Member] Other Specialized REITs [Member] Real Estate Development [Member] Real Estate Operating Companies [Member] Real Estate Services [Member] Retail REITs [Member] Self Storage REITs [Member] Short-Term Investments [Member] Single-Family Residential REITs [Member] Telecom Tower REITs [Member] Investment Type [Axis] American Tower Corp. [Member] CBRE Group, Inc., Class A [Member] Crown Castle, Inc. [Member] Digital Reality Trust, Inc. [Member] Equinix, Inc. [Member] Mitsui Fudosan Co. Ltd. [Member] Prologis, Inc. [Member] Simon Property Group, Inc. [Member] Vivmark Residential [Member] Welltower, Inc. [Member]